Support Revert for Pull Requests that were merged using Squash Merge strategy

Issue Summary

Currently with Bitbucket Cloud, we do not have a way to track what merge strategy was used (commit, FF merge or Squash merge). Currently do not support Revert for PRs that was merged using Squash merge, but present the user with the Option anyways in the UI. 

Steps to Reproduce

1. Create a branch off Main branch of the repo
2. Add commits to the newly created branch
3. Create a PR and merge that PR into a Main branch using Squash merge strategy
4. Then try to revert it, you will be presented with the following error msg, depending on the View you are using (old vs new Pr view)

Expected Results

Provide support for PR Revert for when Squash merge strategy was used. Or remove the Revert option for those PRs. 

Actual Results

We return 400 error in the console when trying to revert Squash merge 

Workaround

The workaround currently is to do a PR revert locally and then push changes to Bitbucket remote repo.