Remove some unused CSS styles (#26852)

1. `icons`: globally searched, no use in templates.
2. toast's `display: inline-block;`: there is a `display: flex` below.

web_src/css/modules/toast.css

@@ -28,7 +28,6 @@
   border-radius: var(--border-radius);
   background: transparent;
   border: none;
-  display: inline-block;
   display: flex;
   width: 30px;
   height: 30px;