Check module_ancestor is persisted
Check module_ancestor is persisted

Add `module_ancestor_load.module_ancestor.persisted?` to
`load_metasploit_module` in case the validator does not check for that
and to make the check explicit as will be done for persisting classes.

rapid7/metasploit-cache,rapid7/metasploit-cache,rapid7/metasploit-cache,rapid7/metasploit-cache