MC-3571: Implement overlay for MC-1405

Fix font-family assignment in order to properly show hide icon

Author: danmooney2

app/code/Magento/PageBuilder/view/adminhtml/web/css/source/_fonts.less

@@ -25,8 +25,7 @@
     @font-style: normal
 );
 
-[class^='icon-pagebuilder-'],
-[class*=' icon-pagebuilder-'] {
+.pagebuilder-icon {
     /* Better Font Rendering =========== */
     -moz-osx-font-smoothing: grayscale;
     -webkit-font-smoothing: antialiased;
@@ -39,3 +38,8 @@
     speak: none;
     text-transform: none;
 }
+
+[class^='icon-pagebuilder-'],
+[class*=' icon-pagebuilder-'] {
+    &:extend(.pagebuilder-icon all);
+}