Fix "array to string" conversion error.

Summary: Fixes T5298. This bug was probably introduced in D9248. It looks like I forgot to update some references to `$version`.

Test Plan: Ran `arc lint --everything` in rPHU.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Maniphest Tasks: T5298

Differential Revision: https://secure.phabricator.com/D9434