Rare instances where an expanded folder that has children appears empty

[david-tejada]

On very rare occasions a folder that has children appears empty. This issue is caused by this vscode bug where TreeView reveal creates a race condition with TreeDataProvider#getChildren. I was able to reproduce this issue fairly consistently by moving a file to a folder that is collapsed and then back.

The modifications in PRs #35 and #36 seem to mitigate this bug since they remove unnecessary calls to TreeView.reveal. This bug seems to be scheduled to be fixed soon so I don't think we need to do anything here. If the bug takes too long to be fixed and the changes in the mentioned PRs don't mitigate the bug enough I could try to add some delays after moving a file so that they refresh call in the file watcher has had enough time to complete. I think I should also only call refresh when the parent entry is expanded anyway.