Fix some CSS scoping issues

mentoring/components/public/css/questionnaire-edit.css

@@ -4,7 +4,3 @@
   height: 30px;
   line-height: 30px;
 }
-
-.wrapper-xblock.level-page .xblock-render {
-	padding: 10px;
-}

mentoring/public/css/mentoring_edit.css

 /* Display of url_name below content */
-.url-name-footer {
+.xblock[data-block-type=mentoring] .url-name-footer {
   font-style: italic;
 }
 
-.url-name-footer .url-name {
+.xblock[data-block-type=mentoring] .url-name-footer .url-name {
   margin: 0 10px;
   font-family: monospace;
 }