bug report with fix: Q&A settings malformed URLs

The Q&A settings page has malformed URLs for the Page Layout images. On this page:
It links to these images:


The "//" should be only "/".

The bad code is in "qa/ui-admin/settings-general.php" on lines 24, 29 and 34. This appears to be the only place in the plugin where the "QA_PLUGIN_URL . '/" string appears.