[DOCUMENTATION] Update user guide for workloads repository

[IanHoang]

We recently experienced GH actions failures which required manual backporting changes. However, we didn't consider how some of branches are more closely tied to main than others. For example, branches 2 and 3 are closely tied to main while 1 and 7 are not.

Manually backporting changes from main to all branches might not be suitable and could cause issues. The same can be said for reverting changes that were applied to all branches. We should avoid backporting "reverted commits" as these can cause issues. Reverting a commit across all branches should be done on a branch-by-branch basis.

Solution

The workloads repository should update its guidance on how to develop and test features, how to properly backport changes when backport GH actions fails, and how to properly revert commits.