What does this MR do?
Refactor time tracking to prepare for multiple assignees sidebar
Are there points in the code the reviewer needs to double check?
Shouldn't be. Time tracking should still work like it used to.
Why was this MR needed?
Prep for multiple assignees sidebar
Sidebar Architecture
Multiple MR Plan
Step 1 - Refactor time tracking out of IIFE
Step 2 - Update specs, Remove subbable resource
Step 3 - Replace single quotes with double quotes in templates
Step 4 - Rename issuable into sidebar
Step 5 - Setup mediator to initialize time tracking
Step 6 - Refactor service and store into separate sidebar service and sidebar store
Step 7 - Add multiple assignees sidebar
Step 8 - Add tests for multiple assignees sidebar