Update purl-types-index.schema.json #609

Reference: #609
Signed-off-by: John M. Horan <johnmhoran@gmail.com>

Author: johnmhoran

schemas/purl-types-index.schema.json

@@ -1,8 +1,8 @@
 {
   "$schema": "http://json-schema.org/draft-07/schema#",
-  "$id": "https://purl-spec.org/schemas/purl-type-index.schema-1.0.json",
+  "$id": "https://packageurl.org/schemas/purl-type-index.schema-1.0.json",
   "title": "Package-URL types index",
-  "description": "A list of the registered Package-URL types.",
+  "description": "An index of registered Package-URL types.",
   "type": "array",
   "additionalItems": false,
   "items": {