[clang] [Clang] Ensure correct template parameter depth for abbreviated templates (PR #209693)

[Corentin Jabot via cfe-commits]

https://github.com/cor3ntin approved this pull request.

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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!

https://github.com/llvm/llvm-project/pull/209693