Disable ASAN in nsupdate for fatal cases
Clang 16 LeakSanitizer reports a memory leak when dns_request_create() returned a TLS error in the nsupdate system test. While technically a memory leak on error handling, it's not a problem because the program is immediately terminated; nsupdate is not expected to run for a prolonged time.
Validation job: https://gitlab.isc.org/isc-projects/bind9/-/jobs/3349975
Closes #4023 (closed)