🎉 Source Github: Extend existing streams with user property (#5156)

* Added User property to certain schemas, updated acceptance-tests, bumped versions

* Added changelog

* moved users.json to the schemas/shared

* add newline to user.json

Co-authored-by: Oleksandr Bazarnov <oleksandr.bazarnov@globallogic.com>

airbyte-integrations/connectors/source-github/source_github/schemas/pull_requests.json

@@ -53,8 +53,8 @@
     "title": {
       "type": ["null", "string"]
     },
-    "user_id": {
-      "type": ["null", "integer"]
+    "user": {
+      "$ref": "user.json"
     },
     "body": {
       "type": ["null", "string"]