add icon in navbar (#748)

Author: dks333

settings.mdx

@@ -227,6 +227,9 @@ This section contains the full reference for the docs.json file.
         <ResponseField name="href" type="string (uri)" required>
           A valid path or external link
         </ResponseField>
+        <ResponseField name="icon" type="string | object">
+          The icon to be displayed in the navbar.
+        </ResponseField>
       </Expandable>
     </ResponseField>
     <ResponseField name="primary" type="object">