2.0.6 upgrade Step 6 fails with SQL syntax error due to unescaped quotes

If an event title contains an apostrophe, then upgrade step 6 (miscellaneous) fails on this query at Upgrade/TwoZero/Form/Step6.php line 104:

$query1 = "SELECT civicrm_participant_payment.participant_id,civicrm_participant_payment.contribution_id FROM civicrm_participant, civicrm_participant_payment where civicrm_participant.event_level = '{$level }' AND civicrm_participant_payment.participant_id = civicrm_participant.id";

Note that $level is not escaped, so if it contains an apostrophe then a SQL syntax error results, e.g.:
where civicrm_participant.event_level = 'Why Can't Equalities Communities Reach Us?'

The attached patch worked for me, however I don't know whether this is the Civi way of doing it.

2.0.6 Drupal PHP5

Dave