[clang] [clang][Parser] "Better" error messages for invalid template template (PR #95726)

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Sirraide wrote:

> This change isnt reflected in that, but I think its probably good enough and not worth worrying about

Hmm, yeah, that’s true, but given that this is mainly about error correction, it’s not too important of a change imo; the program contains an error and won’t compile either way, after all.

https://github.com/llvm/llvm-project/pull/95726