Closing the tab of Pull Request using Ctrl+W shortcut, closes the underlying tab too

[DavideViolante]

• Extension version: 0.15.0
• VSCode Version: 1.43.2
• OS: Ubuntu 18.04

Steps to Reproduce:

1. Open a PR using this extension
2. Try closing the PR tab (not the PR itself) using the keyboard shortcut Ctrl+W (I think on Mac is Cmd+W)
3. This will close VS Code if the PR tab is the only one open, or will close the underlying tab currently opened. The expected behaviour is that Ctrl+W will close the PR tab only.

GIF (I just press Ctrl+W):

I couldnt find the issue already opened, sorry if there is already.

[DavideViolante]

I just noticed that this bug seems related to VS Code itself: microsoft/vscode#86790 and many more similar issues are present in vscode repo already. Closing.