[clang] [clang] Look through alias templates when visiting dependent base classes (PR #223713)

[Christian Kandeler via cfe-commits]

ckandeler wrote:

> This change needs a release note. Please add an entry to `clang/docs/ReleaseNotes.md` in the section the most adapted to the change, and referencing any Github issue this change fixes. Thanks!

Added the release note. I'm not aware of any github issue.

https://github.com/llvm/llvm-project/pull/223713