message: dealing with no parquet files found
diff: @@ -77,6 +77,10 @@ class Staking(Rule):
  self.end_block
  )
  +
  + if table_query == "parquet_scan([])" or aux_table_query == "parquet_scan([])":
  + df = pd.DataFrame(columns=["payee", "rewards"])
  + else:
  df = self.run_query(table_query, vars, aux_table_query)
  df["rewardProgramID"] = reward_program_id
  