Detailed code coverage reporting

[DariuszDepta]

For some time now, the Rust code coverage tool cargo-llvm-cov has been generating high-quality and detailed code coverage statistics. To better reflect this in daily maintenance tasks, a new badge has been added to report more accurate coverage for this crate. The codecov badge was removed due to its lower precision.

A new task named cov-badge was added to Taskfile.yml to automatically generate the more accurate coverage badge for this crate.

The new badge displays three numbers, like: 94% │ 93% │ 95%
These numbers are the truncated coverage percentages for covered regions, executed functions and covered lines respectively. Exactly in the same order like the textual coverage report does when called like this (for MultiTest) in the TOTAL summary line:

$ cargo +stable llvm-cov --no-cfg-coverage --all-features

The example output is like shown below:

Filename                                       Regions    Missed Regions     Cover   Functions  Missed Functions  Executed       Lines      Missed Lines     Cover    Branches   Missed Branches     Cover
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
addresses.rs                                        74                 1    98.65%           9                 0   100.00%          54                 0   100.00%           0                 0         -
api.rs                                             126                 0   100.00%          17                 0   100.00%         116                 0   100.00%           0                 0         -
app.rs                                             473                60    87.32%          50                 3    94.00%         361                38    89.47%           0                 0         -
app_builder.rs                                     278                 0   100.00%          15                 0   100.00%         376                 0   100.00%           0                 0         -
bank.rs                                            854                54    93.68%          26                 2    92.31%         422                23    94.55%           0                 0         -
checksums.rs                                         5                 0   100.00%           1                 0   100.00%           3                 0   100.00%           0                 0         -
contracts.rs                                       279                42    84.95%          39                 6    84.62%         315                41    86.98%           0                 0         -
custom_handler.rs                                   36                 6    83.33%           9                 2    77.78%          52                 6    88.46%           0                 0         -
error.rs                                            48                 0   100.00%          10                 0   100.00%          34                 0   100.00%           0                 0         -
executor.rs                                        131                18    86.26%          12                 1    91.67%         122                13    89.34%           0                 0         -
module.rs                                           33                 0   100.00%          10                 0   100.00%          74                 0   100.00%           0                 0         -
prefixed_storage.rs                                304                 6    98.03%          23                 1    95.65%         146                 3    97.95%           0                 0         -
prefixed_storage/length_prefixed.rs                258                 0   100.00%          12                 0   100.00%         111                 0   100.00%           0                 0         -
prefixed_storage/namespace_helpers.rs              330                 0   100.00%          13                 0   100.00%         134                 0   100.00%           0                 0         -
prefixed_storage/typed_prefixed_storage.rs          74                11    85.14%          15                 3    80.00%          79                12    84.81%           0                 0         -
staking.rs                                        2411               124    94.86%          84                 3    96.43%        1836                42    97.71%           0                 0         -
stargate.rs                                         29                 0   100.00%           8                 0   100.00%         101                 0   100.00%           0                 0         -
test_helpers/caller.rs                              21                 3    85.71%           4                 1    75.00%          28                 5    82.14%           0                 0         -
test_helpers/echo.rs                                81                16    80.25%           7                 3    57.14%          63                 7    88.89%           0                 0         -
test_helpers/error.rs                               25                 3    88.00%           5                 1    80.00%          35                 3    91.43%           0                 0         -
test_helpers/gov.rs                                 25                 3    88.00%           4                 1    75.00%          19                 3    84.21%           0                 0         -
test_helpers/hackatom.rs                            71                15    78.87%           7                 1    85.71%          49                 8    83.67%           0                 0         -
test_helpers/ibc.rs                                 25                 3    88.00%           4                 1    75.00%          18                 3    83.33%           0                 0         -
test_helpers/payout.rs                              64                 6    90.62%           5                 0   100.00%          39                 0   100.00%           0                 0         -
test_helpers/reflect.rs                             58                 4    93.10%           6                 0   100.00%          45                 0   100.00%           0                 0         -
test_helpers/stargate.rs                            21                 3    85.71%           4                 1    75.00%          17                 3    82.35%           0                 0         -
transactions.rs                                    784                 0   100.00%          33                 0   100.00%         304                 0   100.00%           0                 0         -
wasm.rs                                           2353               115    95.11%          87                 3    96.55%        1528                56    96.34%           0                 0         -
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
TOTAL                                             9271               493    94.68%         519                33    93.64%        6481               266    95.90%           0                 0         -

[pinosu]

Nice work! Lgtm