[clang-tools-extra] [clang-tidy] fix `bugprone-narrowing-conversions` false positive for conditional expression (PR #139474)

[Julian Schmidt via cfe-commits]

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5chmidti wrote:

Please add more tests:

- one of the args being, e.g., `int`, since there should still be a warning
- also add those same tests to the C++ tests to cover that they are being handled correctly in both languages

https://github.com/llvm/llvm-project/pull/139474