Hide dropdown menus when users click workflow items

Summary:
In D16157, dropdown menus got an overly-broad check for not closing when an item is clicked.

Specifically, we don't want to close the menu if the item is really opening a submenu, like "Edit Related Objects..." does on mobile.

The check for this is too broad, and also doesn't close the menu if the item has workflow.

Instead, use a narrower check.

Test Plan:

• Menu still stays open when toggling submenus like "Edit Related Objects".
• Menu now closes properly when using workflow items like "Edit Comment" or "Remove Comment".

Reviewers: chad

Reviewed By: chad

Differential Revision: https://secure.phabricator.com/D17210