Added meta tag in CssColors.t

t/CssColors.t

@@ -20,6 +20,10 @@ sub build_structured_answer {
                 options => {
                     list_content => 'DDH.css_colors.content'
                 }
+            },
+            meta => {
+                sourceName => 'Mozilla Developer Network',
+                sourceUrl => 'https://developer.mozilla.org/en-US/docs/Web/CSS/color_value#Color_keywords'
             }
         };
 }