Use metasploit-model that uses rspec 3+
Use metasploit-model that uses rspec 3+

MSP-12669

Removes deprecation warnings from shared examples pulled in from
metasploit-model.

bcook-r7/metasploit_data_models,rapid7/metasploit_data_models,bcook-r7/metasploit_data_models,rapid7/metasploit_data_models,farias-r7/metasploit_data_models,bcook-r7/metasploit_data_models,farias-r7/metasploit_data_models,rapid7/metasploit_data_models,farias-r7/metasploit_data_models