test: run all fuzz regression tests with all sanitizers
We currently have just one sanitizer for tests, asan, but we may add more in
the future. So let's keep the loop over the sanitizers in meson.build, but
just enable all regression cases under all sanitizers. If it fails under one
of them, it might fail under a different one.
In subsequent commits I'll add test cases which might not fail under asan,
but it's good to commit them for future use.
The test names are made more verbose:
256/257 fuzz-dns-packet:oss-fuzz-5465:address OK 0.04 s
257/257 fuzz-dns-packet:issue-7888:address OK 0.03 s