Correctly mark updateStatusMessage method as static

[braders]

Overview

Correctly mark updateStatusMessage method as static

Before

CRM/Event/Form/Participant.php contains the following code, despite updateStatusMessage not being static:

$updateStatusMsg = CRM_Event_BAO_Participant::updateStatusMessage($this->_id,
  $params['status_id'],
  $this->_statusId
);

The updateStatusMessage method is not used elsewhere in CiviCRM core.

After

The updateStatusMessage method is marked as static. This is consistent with other methods in the CRM_Event_BAO_Participant class.

[civibot]

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