[freeipa PR#5041][opened] [Backport][ipa-4-8] ipatests: remove xfail from test_dnssec

[rcritten]

   URL: https://github.com/freeipa/freeipa/pull/5041
Author: rcritten
 Title: #5041: [Backport][ipa-4-8] ipatests: remove xfail from test_dnssec
Action: opened

PR body:
"""
This PR was opened automatically because PR #5031 was pushed to master and backport to
ipa-4-8 is required.
"""

To pull the PR as Git branch:
git remote add ghfreeipa https://github.com/freeipa/freeipa
git fetch ghfreeipa pull/5041/head:pr5041
git checkout pr5041