[clang-tidy] Fix checks filter with warnings-as-errors

Since commit 5d12b13b, warnings are
internally classified as errors which skip the check filters.

One use-case is particularly affected: you cannot selectively disable
clang-analyzer-core checks, they are force-enabled because required by others.
So enabling warning as errors will show new (and unwanted) errors !

Co-authored-by: kiwixz <kiwixz@outlook.com>

Fixes: #61969

Reviewed By: carlosgalvezp

Differential Revision: https://reviews.llvm.org/D146520