Resolve "Work items: Add edit button to progress widget"

What does this MR do and why?

This MR refactors the work item progress widget from inline editing to Edit button patterns. The designs can be found in the related issue

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

How to set up and validate locally

1. In rails console enable work items MVC 2 feature flag

   Feature.enable(:work_items_mvc_2)

2. Go to the project issue page list
3. Create a new objective
4. Change Objective's progress

Related to #429139 (closed)