Auto merge of #12313 - cynicaldevil:tidy-test, r=Wafflespeanut

test-tidy command now ignores files in subdirectories of ignored dirs

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12225 .

I did not add a test for this, instead I added a directory with an empty file inside the ignored directory, and checked whether this file was being ignored or not.

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1 files changed, 0 insertions, 0 deletions

diff --git a/python/tidy/servo_tidy_tests/test_ignored/whee/foo/bar.rs b/python/tidy/servo_tidy_tests/test_ignored/whee/foo/bar.rs
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/python/tidy/servo_tidy_tests/test_ignored/whee/foo/bar.rs