[clang] [Clang][Parser] Don't always destroy template annotations at the end of a declaration (PR #89494)

[Aaron Ballman via cfe-commits]

AaronBallman wrote:

> Oops. I thought there was some latency between clicking the merge button and your latest comment. Should I revert?

No worries, I should have hit `Request Changes` instead of `Comment`. :-) No need to revert yet.

https://github.com/llvm/llvm-project/pull/89494