[clang] [libclang] Add clang_CXXMethod_getQualifiers, clang_Cursor_isConstexpr, and clang_CXXMethod_isExplicitObjectMemberFunction (PR #183305)

[Jannick Kremer via cfe-commits]

https://github.com/DeinAlptraum commented:

Re: Python bindings
One comment on the tests. otherwise LGTM

https://github.com/llvm/llvm-project/pull/183305