[clang] [clang] Warn on signed char array constant conversion (PR #203792)

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filaka771 wrote:

Ping.

CC @cor3ntin @shafik @Fznamznon @AaronBallman.

I fixed the behavior for plain `char`.
Also, I added tests for both signed and unsigned plain `char` configurations.

Could you please take another look?

https://github.com/llvm/llvm-project/pull/203792