Fix renames of tpep_pickup_datetime → tpep_pickup_day (apache#2496)

Follow-up of apache#2265 where
some partition fields were renamed to avoid naming conflicts but the
fixtures were not updated properly.

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# Rationale for this change

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Author: Fokko

tests/avro/test_reader.py

@@ -112,7 +112,7 @@ def test_read_header(generated_manifest_entry_file: str, iceberg_manifest_entry_
                                     {
                                         "field-id": 1001,
                                         "default": None,
-                                        "name": "tpep_pickup_datetime",
+                                        "name": "tpep_pickup_day",
                                         "type": ["null", {"type": "int", "logicalType": "date"}],
                                     },
                                 ],

tests/conftest.py

@@ -1178,7 +1178,7 @@ def metadata_location_gz(tmp_path_factory: pytest.TempPathFactory) -> str:
         "data_file": {
             "file_path": "/home/iceberg/warehouse/nyc/taxis_partitioned/data/VendorID=null/00000-633-d8a4223e-dc97-45a1-86e1-adaba6e8abd7-00001.parquet",
             "file_format": "PARQUET",
-            "partition": {"VendorID": 1, "tpep_pickup_datetime": 1925},
+            "partition": {"VendorID": 1, "tpep_pickup_day": 1925},
             "record_count": 19513,
             "file_size_in_bytes": 388872,
             "block_size_in_bytes": 67108864,
@@ -1677,7 +1677,7 @@ def avro_schema_manifest_entry() -> Dict[str, Any]:
                                     {
                                         "field-id": 1001,
                                         "default": None,
-                                        "name": "tpep_pickup_datetime",
+                                        "name": "tpep_pickup_day",
                                         "type": ["null", {"type": "int", "logicalType": "date"}],
                                     },
                                 ],
@@ -1969,7 +1969,7 @@ def iceberg_manifest_entry_schema() -> Schema:
                         ),
                         NestedField(
                             field_id=1001,
-                            name="tpep_pickup_datetime",
+                            name="tpep_pickup_day",
                             field_type=DateType(),
                             required=False,
                         ),