fix: update contact email

Author: Bloomingg

docusaurus.config.js

@@ -197,7 +197,7 @@ const config = {
               },
               {
                 label: 'Contact Us',
-                href: 'mailto:service@open-im.com',
+                href: 'mailto:contact@openim.io',
               },
             ],
           },

i18n/en/docusaurus-theme-classic/footer.json

@@ -25,7 +25,7 @@
   },
   "link.item.label.Contact Us": {
     "message": "Contact Us",
-    "description": "The label of footer link with label=Contact Us linking to mailto:service@open-im.com"
+    "description": "The label of footer link with label=Contact Us linking to mailto:contact@openim.io"
   },
   "link.item.label.Documentation": {
     "message": "Documentation",