[SSSD] [sssd PR#5797][synchronized] Tests: Install iptabls as its not installed by default

[aborah-sudo]

   URL: https://github.com/SSSD/sssd/pull/5797
Author: aborah-sudo
 Title: #5797: Tests:  Install iptabls as its not installed by default
Action: synchronized

To pull the PR as Git branch:
git remote add ghsssd https://github.com/SSSD/sssd
git fetch ghsssd pull/5797/head:pr5797
git checkout pr5797