Issue title: After renaming a workspace, the panel is not updated until switching back to the workspace
 Issue body: If a workspace is (re)named, the workspace does not change in the panel, and stays "focused" (in the panel) when switching away. When switching to one of these workspaces, the applet seems to refresh all of them, reseting the focus and applying the naming.

 Comments: 
 Comment 0: Yes, it only refreshes the workspace array when you switch workspace. I think there should be some even for rename too. I will look into it.
 Comment 1: Works great now, thanks!
{'source': 'GithubIssues', 'repo_name_with_owner': 'denesb/xfce4-i3-workspaces-plugin', 'issue_id': 81632955, 'repo_stars': 107.0}