[clang] [analyzer] Add an ownership change visitor to StreamChecker (PR #94957)

[Kristóf Umann via cfe-commits]

Szelethus wrote:

> I did not find a similar test for `MallocChecker` but there could be one with similar test functions.

I'm not sure what tests you are referring to. I did fix your other observations.

https://github.com/llvm/llvm-project/pull/94957