Update tableauserverclient/server/endpoint/workbooks_endpoint.py

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: jacalata

tableauserverclient/server/endpoint/workbooks_endpoint.py

@@ -145,7 +145,6 @@ def refresh(self, workbook_item: Union[WorkbookItem, str], incremental: bool = F
         id_ = getattr(workbook_item, "id", workbook_item)
         url = f"{self.baseurl}/{id_}/refresh"
         refresh_req = RequestFactory.Task.refresh_req(incremental, self.parent_srv)
-        server_response = None
         try:
             server_response = self.post_request(url, refresh_req)
         except ServerResponseError as e: