[clang] [LifetimeSafety] Avoid suggesting lifetimebound attribute on primary templates declarations (PR #203866)

[Gábor Horváth via cfe-commits]

https://github.com/Xazax-hun commented:

Overall, sounds like this is what we want to do but I wonder if there is a simpler/more reliable way to do this. 

https://github.com/llvm/llvm-project/pull/203866