Add mxd.is-a.dev domain registration

domains/mxd.json

@@ -0,0 +1,9 @@
+{
+  "owner": {
+    "username": "yugdabgar21",
+    "email": "yugdabgar21@gmail.com"
+  },
+  "records": {
+    "CNAME": "portfolio.yugdabgar21.workers.dev"
+  }
+}