Increase z-index of full-size and navbar-main components (#7286)

GitOrigin-RevId: dec7c507f896a7775fdf71784ad60a8645b2474d

services/web/frontend/stylesheets/app/editor.less

@@ -51,6 +51,7 @@
   bottom: 0;
   left: 0;
   right: 0;
+  z-index: 1;
 }
 
 .global-alerts {

services/web/frontend/stylesheets/components/navbar.less

@@ -84,7 +84,7 @@
 }
 
 .navbar-main {
-  z-index: 1;
+  z-index: 2;
   .container-fluid > .navbar-collapse {
     // High specificity needed to override Bootstrap's default.
     margin: 10px 0 0;