R1:5d0222d532c1

Fix an issue where the profile menu could become enormous

Summary: Ref T10054. Without `max-width`, Safari can make this too large with a long project name (maybe because of `table-cell`?).

Test Plan: Saw normal-width menu instead of huge menu on very long project.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10054

Differential Revision: https://secure.phabricator.com/D15046