Adding copilot IVA requests to posting

copilot/posting/copilotux/authorization.py

@@ -0,0 +1,15 @@
+from posting import Posting
+import httpx
+
+
+def on_response(response: httpx.Response, posting: Posting) -> None:
+    # Raise an exception if the request failed
+    response.raise_for_status()
+    # Set a variable to be used in later requests.
+    # You can write '$auth_token' in the UI and it will be substituted with
+    # the value of the $auth_token variable.
+    
+    access_token = response.json().get("access_token")
+    print ("Successfully obtained access_token")
+
+    posting.set_variable("access_token", access_token)