Give visual feedback when a Drydock resource or lease is releasing

Summary: Ref T9252. Show the user when a resource or lease has a pending release command in queue.

Test Plan: Released a resource and lease from the web UI. In both cases, saw a "releasing" tag and the action disable.

Reviewers: hach-que, chad

Reviewed By: chad

Maniphest Tasks: T9252

Differential Revision: https://secure.phabricator.com/D14177