[clang] [libclang/python] Add equality comparison operators for File (PR #130383)

[Jannick Kremer via cfe-commits]

DeinAlptraum wrote:

As for investigation:
I wrote four tests in `test_file.py` that just assert all files as equal (the ones named `test_file_eq_failing...`) which is expected to fail, and all four of these tests fail for me locally. But in the CI, it seems that indeed all in-memory files seem to be treated as equal, while files read from disk are correctly unique.

https://github.com/llvm/llvm-project/pull/130383