Add firewall instructions for redhat

[cbaxley]

Add the missing instructions for redhat and test.

content/docs/markdown/agents/wazuh-agent-management.md
Major section missing Red Hat support:
Line 97: Section titled "Steps to Enroll a Wazuh Agent (Debian-Based Systems)" - needs equivalent Red Hat section
Lines 108-139: All commands use apt-get, repository setup is Debian-specific - needs complete Red Hat equivalent section

[cbaxley]

When working with getting the nftables and firewall commands to work, the docker builds started failing. It was found that iptables needed to be in the docker images now to deal with the create certs.

[cbaxley]

Firewall scripts added and functioning for both nftables and firewalld.