Don't refresh table in the for-loop (#874)

Author: Fokko

tests/integration/test_writes/test_partitioned_writes.py

@@ -170,7 +170,6 @@ def test_query_filter_appended_null_partitioned(
     assert tbl.format_version == format_version, f"Expected v{format_version}, got: v{tbl.format_version}"
     df = spark.table(identifier)
     for col in TEST_DATA_WITH_NULL.keys():
-        df = spark.table(identifier)
         assert df.where(f"{col} is not null").count() == 6, f"Expected 6 non-null rows for {col}"
         assert df.where(f"{col} is null").count() == 3, f"Expected 3 null rows for {col}"
     # expecting 6 files: first append with [A], [B], [C],  second append with [A, A], [B, B], [C, C]