[llvm] [FileCheck] Inline destructor to avoid missing symbol with hidden visibility (PR #225978)

[Fabrice de Gans via llvm-commits]

https://github.com/Steelskin commented:

I looked into this, and this is actually the right approach. TIL. Just a comment from me to prevent these issues in the future.

https://github.com/llvm/llvm-project/pull/225978