[clang] [Clang] fix parser recovery for invalid static_assert string messages (PR #187859)

[Corentin Jabot via cfe-commits]

cor3ntin wrote:

@a-tarasyuk while we might want to think more about `BalancedDelimiterTracker` deal with semi-colon, the fix here is correct (and it's not clear we can do much better than what you do here)

So i think we should land this.

https://github.com/llvm/llvm-project/pull/187859