b707af1 ipatests: do not set dns_lookup to true

Authored and Committed by sorlov 3 years ago
    ipatests: do not set dns_lookup to true
    
    dns_lookup was set to false during ipa client installation which prevented
    searches for SRV records for Kerberos servers.
    Since https://pagure.io/freeipa/issue/6523 is fixed, dns_lookup is always True
    now and the fixture is not needed anymore.
    
    Reviewed-By: Francois Cami <fcami@redhat.com>