LibRegex: Use `NO_UNIQUE_ADDRESS` in RegexMatch for Windows support

[ayeteadoe]

I found a spot not using NO_UNIQUE_ADDRESS when trying to build some AK unit tests on Windows. This macro properly uses the required [[msvc::no_unique_address]].

Also note that Clang version 18+ is required to build on Windows as [[msvc::no_unique_address]] was not supported in clang-cl until then, and since the documentation also uses clang-19 in the compiler installation example, I updated the remaining references to clang-17 to be clang-19 for consistency