[clang] [libclang/python] Expose Rewriter to the python binding (PR #77269)

[Jimmy Z via cfe-commits]

jimmy-zx wrote:

Both tests are just invoking the functionalities of the rewriter on a sample code. I think additional tests for libclang does not provide extra coverage (as it is just the front-end). Thus I mirrored the tests back to the Python binding in 7a4ebf9c8c9ffa29d7f7f863d9a19bfe53432348.

https://github.com/llvm/llvm-project/pull/77269