[clang-tools-extra] [clang-tidy][readability-container-contains] Extend to any class with contains (PR #107521)

[Julian Schmidt via cfe-commits]

https://github.com/5chmidti commented:

> I applied this modified version to llvm-project root

One PR per subproject seems to be the preferred way, judging by the responses to some of those *all of llvm* PRs. IMO, this is a readability cleanup and would probably be accepted.

https://github.com/llvm/llvm-project/pull/107521