[clang] [analyzer] Remove inaccurate legacy handling of bad bitwise shifts (PR #66647)

[Balazs Benics via cfe-commits]

steakhal wrote:

I think I'm fine with the numbers. Note that I could not inspect individual reports because the URL likely refers to some internal server on your side.
Anyway, I'd recommend keeping the test files for two reasons:
  - It's probably not a big deal, we are talking about ~150 lines if I'm not mistaken.
  - It gives an example of how the reports will change: how they looked before and how they will from now on. This is useful for folks rebasing internal forks and wondering what happened with these reports.

https://github.com/llvm/llvm-project/pull/66647