If a local include does not point to a file in the repository, it should
be a system include instead. This is now checked on every commit.
While this does introduce significant overhead in terms of percentage,
I think that an additional 10ms on huge commits (or less on smaller
commits) are acceptable:
hyperfine -w1 './Meta/check-style.py AK/*.h AK/*.cpp' # Before
Benchmark 1: ./Meta/check-style.py AK/*.h AK/*.cpp
Time (mean ± σ): 20.3 ms ± 0.4 ms [User: 17.1 ms, System: 3.
5 ms]
Range (min … max): 19.5 ms … 21.6 ms 128 runs
hyperfine -w1 './Meta/check-style.py AK/*.h AK/*.cpp' # After
Benchmark 1: ./Meta/check-style.py AK/*.h AK/*.cpp
Time (mean ± σ): 32.3 ms ± 0.4 ms [User: 27.9 ms, System: 4.
4 ms]
Range (min … max): 31.4 ms … 34.9 ms 91 runs