feat: Added 'giovanni' subdomain

Added the subdomain for my personal website, hosted on Github Pages.

domains/giovanni.json

@@ -0,0 +1,13 @@
+{
+    "owner": {
+        "username": "ItachiSan",
+        "email": "giovannisantini93@yahoo.it",
+        "twitter": "santini__gio",
+        "discord": "ItachiSan#2408"
+    },
+    "description": "is-a.dev subdomain for my personal blog",
+    "repo": "https://github.com/ItachiSan/itachisan.github.io",
+    "record": {
+        "CNAME": "itachisan.github.io"
+    }
+}