Add TXT record for domain verification

domains/mustapha-boulefa.json

@@ -4,6 +4,9 @@
         "email": "mustapha.boulefa@gmail.com"
     },
     "records": {
-        "CNAME": "portfolio-gold-two-qt4nmphny8.vercel.app"
+        "CNAME": "portfolio-gold-two-qt4nmphny8.vercel.app",
+        "TXT": {
+            "_vercel": "vc-domain-verify=mustapha-boulefa.is-a.dev,bd90b5d3373958d0b0ef"
+        }
     }
 }