[clang-tools-extra] [clang-tidy] Clarify diagnostics of bugprone-sizeof-expression (PR #95550)

[Piotr Zegar via cfe-commits]

PiotrZSL wrote:

Main reason why I pointed out that I do not like ':' character and would prefer ',' or ';' is that:
- no other check is using it
- could in theory cause an issue for some tools that parse warnings because ': ' characters are after "warning" and basically almost never happen in message itself.

https://github.com/llvm/llvm-project/pull/95550