Sort Spaces dropdown by name, not "alphabetical ID"

Summary:
Fixes T10414. I think this sorted by name at one time (the asort()) but then I probably added "Space SX" in front of it. Or I just got this wrong from the beginning.

Instead, sort by space name.

Test Plan: {F1126034}

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10414

Differential Revision: https://secure.phabricator.com/D15334