Often code needs to know that it's built with sanitizers.
There are two common use for such information:
1. Work around incompatibility with sanitizers
2. Use sanitizers for more aggressive bug detection

With the current `ABSL_HAVE_*_SANITIZER` we can't distinguish
this two cased, and we didn't need that before.

Now user can define `NDEBUG_SANITIZER` to ask code like this
to avoid unnecessary checks.

I am not 100% sure that `NDEBUG` is not enough.
However relying on `NDEBUG` today will relax many tests, which
runs in NDEBUG mode only. So new `NDEBUG_SANITIZER` is safer
approach.

PiperOrigin-RevId: 619268413
Change-Id: I58185cd6886593a3742b8424deccdec366c2a35a