[clang] [CIR][NFC] EHScope & Cleanups Iterators and operators overloading (PR #165317)

[Andy Kaylor via cfe-commits]

https://github.com/andykaylor commented:

This needs a test, which means it has to be introduced with (or after) something that mixes EH scopes with normal cleanups.

https://github.com/llvm/llvm-project/pull/165317