If you are on a branch that has a PR where you don't have the remote associated with its head ref, Launchpad view can show an "Unable to open details for PR #${pullRequest.id} because of a missing remote." prompt and ask you to add a remote.

This occurs because in Launchpad view, we always fully expand the "current branch" PR node, and expanding the PR node means finding its remote/repo info. Usually the GitHub PR extension hides this issue because it retrieves the virtual repo.

To reproduce:

1. Have GitHub PR extension disabled.
2. Be on a branch with a PR where you don't have the remote of the headref.
3. Load GitLens with Launchpad view open and visible.

We should suppress this and not expand the PR node when the remote isn't available.