Extend ApprovalRules::CreateService to support group target

What does this MR do and why?

It updates the ApprovalRule::CreateService to support ApprovalGroupRules.

The major change is using the BaseContainerService as the base service for the approval rule services. This allows group to be passed as a parameter to the CreateService. Other services will be updated in future iterations.

How to set up and validate locally

This MR adds new functionality to a service which is not yet exposed via an API. So the best way to test locally is to run the specs for the service. Existing functionality for approval rules should not be affected.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #430096 (closed)