[clang-tools-extra] [clang-tidy] Add new performance-use-starts-ends-with check (PR #72385)

[Nicolas van Kempen via cfe-commits]

nicovank wrote:

Major changes:
 -  Now matching on any class that has a `starts_with`, `startsWith`, or `startswith` function. This is done in order (prioritising functions in subclasses, but this could be changed). Experimenting on making this an option, not sure it's worth it without controlling class names as well.
 -  Not using `Lexer::getSourceText` anymore.

https://github.com/llvm/llvm-project/pull/72385