Add GitLens troubleshooting guide for Bitbucket pull requests

(#4192)

Author: gkchiv

_images/gl-troubleshooting-bitbucket-pr-commit-links.png

@@ -0,0 +1,23 @@
+---
+title: GitLens Troubleshooting
+description: GitLens Troubleshooting
+taxonomy:
+  category: gitlens
+---
+
+## Enable showing Bitbucket pull request for a commit
+
+GitLens can show a Pull Request for a commit for a connected integration. But Bitbucket [requires](https://developer.atlassian.com/cloud/bitbucket/rest/api-group-pullrequests/#api-repositories-workspace-repo-slug-commit-commit-pullrequests-get)
+a Pull Request Commit Links app to be installed in the workspace to enable this feature.
+
+It's not a real application that can be seen in workspace settings, it's rather an internal service that Bitbucket activates after some event,
+so for a user it is just a part of the Bitbucket service.
+
+To enable this feature, you need to visit any commit in the Bitbucket UI and click on the "Pull requests" link in the "Apps" section at the bottom-right of the page:
+
+<img src="/wp-content/uploads/gl-troubleshooting-bitbucket-pr-commit-links.png" class="help-center-img img-bordered">
+
+The click makes the application is activated and its takes some time for Bitbucket to index data on their side.
+After that PullRequests for commits will be shown in GitLens:
+
+<img src="/wp-content/uploads/gitlens-troubleshooting-bitbucket-pr-on-a-commit.png" class="help-center-img img-bordered">