chore: default compiler.enableNew to false until development restarts

[Kha]

No description provided.

[leanprover-community-mathlib4-bot]

• ❗ Mathlib CI will not be attempted unless you rebase your PR onto the 'nightly' branch. (2023-12-06 10:29:37)
• ✅ Mathlib branch lean-pr-testing-3034 has successfully built against this PR. (2023-12-20 23:22:11) View Log
• ✅ Mathlib branch lean-pr-testing-3034 has successfully built against this PR. (2023-12-21 00:57:42) View Log

[Kha]

@leodemoura There is a number of tests testing new compiler output that are now broken. We could disable the option for external users only but I think the time savings for building Lean itself are significant enough to justify moving these tests into a new folder that is not part of the suite for now.

[Kha]

I've moved the new compiler tests to a separate directory that is currently not included in the test suite

[Kha]

!bench

[leanprover-bot]

Here are the benchmark results for commit 3d00588.
There were significant changes against commit 79c7b27:

  Benchmark                  Metric         Change
  =============================================================
+ import Lean                branches        -5.7%   (-211.8 σ)
+ import Lean                instructions    -5.9%   (-276.7 σ)
+ import Lean                maxrss         -16.6%  (-1346.8 σ)
+ lake build no-op           maxrss          -7.6%   (-165.8 σ)
+ lake config elab           instructions   -31.7%  (-3373.8 σ)
+ lake config elab           maxrss         -12.5%   (-359.6 σ)
+ lake config elab           task-clock     -25.5%    (-35.4 σ)
+ lake config elab           wall-clock     -25.4%    (-36.1 σ)
+ lake config import         instructions    -2.5%   (-208.2 σ)
+ lake config import         maxrss         -12.2%   (-406.3 σ)
+ lake config tree           instructions    -3.1%    (-59.2 σ)
+ lake config tree           maxrss         -12.5%   (-368.9 σ)
+ lake env                   instructions    -2.5%    (-96.8 σ)
+ lake env                   maxrss         -12.2%   (-307.3 σ)
+ reduceMatch                instructions    -2.8%  (-1142.9 σ)
+ reduceMatch                maxrss         -15.8%  (-1341.6 σ)
+ stdlib                     instructions   -30.5% (-69991.5 σ)
+ stdlib                     maxrss         -11.2%    (-23.4 σ)
+ stdlib                     task-clock     -26.7%   (-105.8 σ)
+ stdlib                     wall-clock     -28.1%    (-37.8 σ)
+ stdlib size                bytes .olean   -30.1%
+ tests/bench/ interpreted   instructions    -3.7%  (-2690.3 σ)
+ tests/bench/ interpreted   maxrss         -15.6%   (-729.8 σ)
+ tests/bench/ interpreted   task-clock      -8.0%    (-10.1 σ)
+ tests/bench/ interpreted   wall-clock      -6.9%    (-14.4 σ)
+ workspaceSymbols           instructions    -1.8%  (-3704.7 σ)
+ workspaceSymbols           maxrss         -17.3%   (-990.1 σ)