Crash when deleting a repo-folder on disk, if SourceGit has it open in a tab (same when removing a Worktree) #1436
Description
When deleting a repo-folder on disk, while SourceGit has that folder open in a tab/page, we'll get a crash in Repository.RefreshBranches(), on this line: CurrentBranch = branches.Find(x => x.IsCurrent);
Repository.CurrentBranch.set doesn't check (after calling SetProperty()) if the NEW value of _currentBranch is null, before trying to access its Head property. Could be fixed by using _currentBranch?.Head, but we should check that there are no follow-up errors due to there being no branches (and no repo) anymore.
NOTE: I found this crash when I removed a Worktree (from within SourceGit UI) while that Worktree was still open in another tab.