Consolidate project and MR approval rules editing

Summary

Currently different interface is used for project and MR level editing. For project, edit is done immediately when a rule is changed. For MR, edit is only applied when the whole MR form is submitted.

The two copies of logic to do similar things has slowed down development considerably. We could consider if DRY the action using one implementation is valuable.

Improvements

Less code and sharing the same behavior/code when editing MR and project.

Risks

UI wise this may be unexpected since behavior would change.

Involved components

• javascript
• api endpoints