Modify `1.2.3 Ensure that the DenyServiceExternalIPs is set` in CIS-1.7/1.8

[andypitcher]

Parent: https://github.com/aquasecurity/kube-bench/issues/1606

Context: In CIS-1.7 and CIS-1.8 (master 1.2.3 Ensure that the DenyServiceExternalIPs is set) the operand is wrong and makes the check to WARN even if --enable-admission-plugins=DenyServiceExternalIPs is properly set.

This PR makes the following change to master 1.2.3 check for CIS-1.7 and CIS-1.8:

• op changed from have to has and removed bin_op: or
• remediation description changed to only include --enable-admission-plugins