Update docusaurus.config.js

Author: shalithasuranga

docusaurus.config.js

@@ -117,6 +117,10 @@ module.exports = {
               label: 'Contact CodeZri',
               href: 'https://forms.gle/mTxB9gdKsdWPkwBQA',
             },
+            {
+              label: 'Design guide',
+              href: 'https://github.com/codezri/design-guide'
+            },
             {
               label: 'Privacy policy',
               to: 'privacy-policy',