Merge pull request #4033 from nhsuk/fix-missing-dev-tools-styles

Fix missing styles for dev tools

Author: thomasleese

app/assets/stylesheets/components/_index.scss

@@ -5,6 +5,7 @@
 @forward "button";
 @forward "card";
 @forward "count";
+@forward "dev-tools";
 @forward "environment";
 @forward "filters";
 @forward "header";