Fix SCSS linting issues (#2207)

* Disable font-family-no-missing-generic-family-keyword for font-awesome accessibility icons

* Run stylelint --fix

* Avoid `@extend` directives with doodle modal CSS

* Drop use of `@extend` for notification cleanup buttons SCSS

* Run prettier on SCSS

app/javascript/flavours/glitch/styles/components/drawer.scss

@@ -229,7 +229,7 @@
     cursor: inherit;
   }
 
-  @media screen and (min-height: 640px) {
+  @media screen and (height >= 640px) {
     display: block;
   }
 }