Edit Issue and Merge Request Description

Problem to Solve

Currently Issues and Merge Request descriptions are available to see inside of VS Code through the webview components. However, it's not possible to edit these issues and merge requests, instead requiring a user to open them in their GitLab instance to make any changes.

Proposal

It should be possible to open an existing issue or merge request inside of VS Code and click an edit button that allows you to edit the contents of that item.