[clang] [NFC][analyzer] Conversion to CheckerFamily: RetainCountChecker (PR #152138)

[Balazs Benics via cfe-commits]

https://github.com/steakhal commented:

I don't think I have much to say here. Maybe, thank you :)
I'm not too interested reviewing this. I scrolled through and in that 2 minutes I didn't spot any issues. Do a review and merge it.

https://github.com/llvm/llvm-project/pull/152138