Renamethreat_monitoring_path to policies_path

Summary

so that I did not need to copy the policy_editor component for the :security_orchestration_policies_configuration feature, I did not rename the threat_monitoring_path to policies_path in https://gitlab.com/gitlab-org/gitlab/blob/master/ee/app/helpers/projects/security/policies_helper.rb#L38, even though the policies are out of the threat monitoring group

Improvements

The path will be easier to read for developers

Risks

If done before the feature flag is removed, it will prevent us from rolling the feature flag back in the event of an issue

Involved components

• https://gitlab.com/gitlab-org/gitlab/blob/master/ee/app/helpers/projects/security/policies_helper.rb#L38

and the following files