[ticket/13006] Add variables to the 'core.modify_quickmod_actions' event

Add $quickmod and $action variables
for the 'core.modify_quickmod_actions' event trigerring
to avoid of using global operator in corresponding extensions.

This PR is an addition to the PR https://github.com/phpbb/phpbb/pull/2045.

<a href="https://tracker.phpbb.com/browse/PHPBB3-13006">PHPBB3-13006</a>.