Add comma to fix syntax error

Created by: brienneK

Overview

An error is being triggered by a missing comma in CRM/Contributionrecur/Form/PageSettings.php.

Before / Replication Steps

If a user goes to the 'Recurring' tab on a Contribution page, the contents of that tab do not load and they receive a 'network error' message in the upper right corner.

After

With this syntax fix, the user does not encounter an error when loading the 'Recurring' tab on a Contribution page.

Additional Information

There is another error at play here that is not addressed by this PR. When a user clicks Save on this form, the page displays a message that 'No contributions pages have been created yet'. There is a work around to go back to Manage Contribution Pages and edit the desired page again, but the user should not have to back track to make edits after saving.