fix: do not remove destinationTable from job config (googleapis#483)

Author: dinigo

google/cloud/bigquery/client.py

@@ -47,7 +47,6 @@
 from google.cloud import exceptions
 from google.cloud.client import ClientWithProject
 
-from google.cloud.bigquery._helpers import _del_sub_prop
 from google.cloud.bigquery._helpers import _get_sub_prop
 from google.cloud.bigquery._helpers import _record_field_to_json
 from google.cloud.bigquery._helpers import _str_or_none
@@ -1726,7 +1725,6 @@ def create_job(self, job_config, retry=DEFAULT_RETRY, timeout=None):
             )
         elif "query" in job_config:
             copy_config = copy.deepcopy(job_config)
-            _del_sub_prop(copy_config, ["query", "destinationTable"])
             query_job_config = google.cloud.bigquery.job.QueryJobConfig.from_api_repr(
                 copy_config
             )