docs: update .all-contributorsrc

Author: allcontributors[bot]

.all-contributorsrc

@@ -697,6 +697,15 @@
         "code",
         "ideas"
       ]
+    },
+    {
+      "login": "Dennis273",
+      "name": "Dennis Chen",
+      "avatar_url": "https://avatars.githubusercontent.com/u/19815164?v=4",
+      "profile": "https://github.com/Dennis273",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "repoHost": "https://github.com",