Minor change to the Celerity map formatting

Summary: Add a new line for clarity.

Test Plan: Inspected `./resources/celerity/map.php`.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9931