[9.11] Disable dnstap testing globally
The dnstap system test fails permanently. Given that we don't have the resources to investigate and fix the issue in this EoL branch, turn off dnstap globally.
I:dnstap:checking that named-checkconf detects no error in good-fstrm-set-reopen-interval.conf
I:dnstap:wait for servers to finish loading
I:dnstap:checking initial message counts
I:dnstap:checking UDP message counts
I:dnstap:ns3 3 expected 4
I:dnstap:failed
I:dnstap:checking TCP message counts
I:dnstap:checking AUTH_QUERY message counts
I:dnstap:checking AUTH_RESPONSE message counts
I:dnstap:checking CLIENT_QUERY message counts
I:dnstap:checking CLIENT_RESPONSE message counts
I:dnstap:ns3 1 expected 2
I:dnstap:failed
But enable dnstap in Debian "stretch" CI jobs to ensure it builds and gets at least minimal testing.