fix: Remove duplicate key time_partitioning from Table._PROPERTY_TO_A… (#1898)

…PI_FIELD

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Fixes #<issue_number_goes_here> 🦕

Author: toransahu

google/cloud/bigquery/table.py

@@ -385,7 +385,6 @@ class Table(_TableBase):
         "clone_definition": "cloneDefinition",
         "streaming_buffer": "streamingBuffer",
         "self_link": "selfLink",
-        "time_partitioning": "timePartitioning",
         "type": "type",
         "view_use_legacy_sql": "view",
         "view_query": "view",