Remove "exit workspace" part of the Save workspace button action

[ggeisler]

I'm a little on the fence with this one so if anyone has thoughts contrary to what I'm proposing, feel free to say so.

Currently when the user selects the "Save workspace" action (when working in a Mirador workspace) that action does two things (from the user perspective):

• Saves the current workspace state (snapshot)
• Exits the workspace and redirects the user to the details page of the workspace

I think we should only do the first of those -- update the workspace snapshot -- but not the second. We should remain in the workspace.

My concern is that especially when doing real annotation editing, users are likely to select the "Save workspace" button at times when all they intend to do is the labelled action: save the workspace. Based on how many software applications work, when users see a "Save workspace" button they are likely to use it just to make sure they don't lose work they've been doing (even though in Mise they are not really in danger of losing annotation editing work that way). And if they're not really done with their workspace work, it's pretty annoying to find yourself on the Workspace details page and having to open the workspace again.

The tradeoff is sometimes a user will want to do what the current action does do: save the workspace state and exit the workspace. In that case, we'd be requiring an extra action, since they'd have to select the "Back" action after the "Save workspace" action. But that feels to me like a more expected flow than the "Save workspace" button doing both things at once.

[mjgiarlo]

Unassigning for now as I'm focused on hiring atm.