[Glitch] Update SCSS of admin and setting pages

Port the SCSS changes from 18d4e03e6b to glitch-soc

app/javascript/flavours/glitch/styles/admin.scss

@@ -105,6 +105,16 @@
       margin-bottom: 30px;
     }
 
+    h4 {
+      text-transform: uppercase;
+      font-size: 13px;
+      font-weight: 500;
+      color: $ui-primary-color;
+      padding-bottom: 8px;
+      margin-bottom: 8px;
+      border-bottom: 1px solid lighten($ui-base-color, 8%);
+    }
+
     h6 {
       font-size: 16px;
       color: $ui-secondary-color;

app/javascript/flavours/glitch/styles/forms.scss

@@ -22,16 +22,6 @@ code {
     margin-top: 4px;
   }
 
-  h4 {
-    text-transform: uppercase;
-    font-size: 13px;
-    font-weight: 500;
-    color: $ui-primary-color;
-    padding-bottom: 8px;
-    margin-bottom: 8px;
-    border-bottom: 1px solid lighten($ui-base-color, 8%);
-  }
-
   p.hint {
     margin-bottom: 15px;
     color: $ui-primary-color;