[clang-tools-extra] [clang-tidy] Added check 'bugprone-function-visibility-change' (PR #140086)

[Baranov Victor via cfe-commits]

https://github.com/vbvictor commented:

I think we should make change the name of the check to include "method" or "member-function" words in it. It will make clear that we check for methods visibility and not some visibility attributes on functions.
Possible names:
bugprone-member-function-visibility-change
bugprone-virtual-member-function-visibility-change
bugprone-visibility-change-to-virtual-member-function (imho the best)
 

https://github.com/llvm/llvm-project/pull/140086