[clang-tidy] Add a fully custom message to `bugprone-unsafe-functions` (#162443)
In some cases, such as when recommending the compiler option
_FORTIFY_SOURCE, the current custom message format is clunky. Now, when
the reason starts with `>`, the replacement string is omitted., so only
the Reason is shown.
`^function$,,has a custom message;` - function 'function' has a custom
message; it should not be used
`^function$,,>has a custom message and no replacement suggestion;` -
function 'function' has a custom message and no replacement suggestion
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Co-authored-by: DonĂ¡t Nagy <donat.nagy@ericsson.com>