Added conversion for str for git timestamps

[markovamaria]

Added conversion to avoid error during testing triggering:

$ redis-benchmarks-spec-cli --use-branch --from-date 2023-02-11  --redis_port 12010 --redis_host *** --redis_pass *** --redis_user default
Traceback (most recent call last):
  File "/home/ubuntu/.local/bin/redis-benchmarks-spec-cli", line 8, in <module>
    sys.exit(main())
  File "/home/ubuntu/.local/lib/python3.8/site-packages/redis_benchmarks_specification/__cli__/cli.py", line 53, in main
    trigger_tests_cli_command_logic(args, project_name, project_version)
  File "/home/ubuntu/.local/lib/python3.8/site-packages/redis_benchmarks_specification/__cli__/cli.py", line 259, in trigger_tests_cli_command_logic
    ) = request_build_from_commit_info(
  File "/home/ubuntu/.local/lib/python3.8/site-packages/redis_benchmarks_specification/__common__/builder_schema.py", line 151, in request_build_from_commit_info
    raise Exception(
Exception: Type of field commit_datetime is not bytes, string, int or float. Type (<class 'datetime.datetime'>). Value=2023-02-21 18:58:55+02:00

[markovamaria]

@filipecosta90, could you please look at change? it was required to remove variable which never used in stats.py to make tests in CI passing. If this should be fixed in another way, please let me know.

[filipecosta90]

@markovamaria why was this removed?

[markovamaria]

@markovamaria why was this removed?

It is assigned, but never used. This line causing fail in .tox tools.

Fail in actions in here: https://github.com/redis/redis-benchmarks-specification/actions/runs/4246038262

Manual repro:

$ .tox/integration-tests/bin/flake8 redis_benchmarks_specification 
redis_benchmarks_specification/__cli__/stats.py:341:9: F841 local variable 'priority_list_usecs' is assigned to but never used 

[markovamaria]

@markovamaria why was this removed?
I agree that it is separate issue. :) But it blocked CI for this commit

[markovamaria]

@filipecosta90, so what do you think, may I keep removing of unused var in this PR or should do separate one? Alternatively need to use this variable somehow..