Add nishant.is-a.dev subdomain pointing to anirul.vercel.app

- This commit adds the DNS configuration for the subdomain nishant.is-a.dev.
- The subdomain is set up as a CNAME pointing to anirul.vercel.app hosted on Vercel.

domains/nishant.json

@@ -0,0 +1,9 @@
+{
+  "owner": {
+    "username": "nishant-sheoran",
+    "email": "nishantsheoran1429@gmail.com"
+  },
+  "records": {
+    "CNAME": "anirul.vercel.app"
+  }
+}