Get rid of .clang-tidy in tests directory #4484

Job	Run time
pre-commit / check-file-sizes	6s
pre-commit / pre-commit	2m 2s
windows / msvc-build (Release)	2m 32s
windows / msvc-build (Debug)	3m 8s
windows / clang-build	2m 35s
ubuntu / clang-build (ubuntu-24.04)	2m 41s
mac / clang-build (Release)	2m 1s
ubuntu / gcc-build (ubuntu-24.04, Release)	2m 21s
ubuntu / gcc-build (ubuntu-24.04, Debug)	2m 10s
mac / clang-build (Debug)	2m 33s
ubuntu / gcc-test (ubuntu-24.04)	8m 23s
mac / clang-test	4m 22s
windows / clang-test	2m 53s
ubuntu / clang-test (ubuntu-24.04)	8m 27s
ubuntu / clang-sanitizer-build (ubuntu-24.04)	3m 18s
windows / msvc-test	4m 54s
windows / clang-test-extended	3m 2s
ubuntu / clang-sanitizer-test (ubuntu-24.04)	2m 51s
mac / clang-test-extended	2m 51s
windows / msvc-test-extended	3m 5s
ubuntu / clang-sanitizer-test-extended (ubuntu-24.04)	2m 23s
ubuntu / gcc-test-extended (ubuntu-24.04)	4m 30s
ubuntu / clang-test-extended (ubuntu-24.04)	4m 29s
ubuntu / gcc-build-codecov	7m 16s
perf / macos-clang-build-perf-stats	2m 6s
perf / ubuntu-gcc-build-perf-stats	1m 30s
pages / build-scoreboard	17s
pages / build-doxygen-xml	20s
pages / build-sphinx	40s
pages / deploy-pages	-1s
	1h 29m 45s

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