feat: add the pattern properties

extensions/linkedin/0.1.0/schema.json

@@ -1,8 +1,9 @@
 {
     "type": "string",
+    "format": "uri",
     "patternProperties": {
         "x-linkedin":{
-            "$ref": "^https://(www\\.)?linkedin\\.com*$"
+            "$ref": "^https://(www\\.)?linkedin\\.com.*$"
         }
     },
     "description": "This extension allows you to provide the Linkedin profile URL of the account representing the team/company of the API.",