Redirect natya.is-a.dev to natya.dev

The old GitHub Pages portfolio (studiousgamer.github.io) is gone;
the portfolio now lives on Cloudflare at natya.dev, so switch the
CNAME record to a URL redirect. Also updates the owner username on
this file and the leftover GitHub Pages verification record from
the old studiousgamer account to the current natyavidhan account.

domains/_github-pages-challenge-studiousgamer.natya.json

@@ -1,6 +1,6 @@
 {
   "owner": {
-    "username": "studiousgamer",
+    "username": "natyavidhan",
     "email": "natyavidhanbiswas10@gmail.com"
   },
   "records": {

domains/natya.json

@@ -1,10 +1,10 @@
 {
   "owner": {
-    "username": "studiousgamer",
+    "username": "natyavidhan",
     "email": "natyavidhanbiswas10@gmail.com",
     "twitter": "GamerStudious"
   },
   "records": {
-    "CNAME": "studiousgamer.github.io"
+    "URL": "https://natya.dev"
   }
 }