nit: Clean up import in conftest.py (#1848)

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Author: Fokko

tests/conftest.py

@@ -48,7 +48,6 @@
 import pytest
 from moto import mock_aws
 
-from pyiceberg import schema
 from pyiceberg.catalog import Catalog, load_catalog
 from pyiceberg.catalog.noop import NoopCatalog
 from pyiceberg.expressions import BoundReference
@@ -140,7 +139,7 @@ def pytest_addoption(parser: pytest.Parser) -> None:
 
 @pytest.fixture(scope="session")
 def table_schema_simple() -> Schema:
-    return schema.Schema(
+    return Schema(
         NestedField(field_id=1, name="foo", field_type=StringType(), required=False),
         NestedField(field_id=2, name="bar", field_type=IntegerType(), required=True),
         NestedField(field_id=3, name="baz", field_type=BooleanType(), required=False),
@@ -151,7 +150,7 @@ def table_schema_simple() -> Schema:
 
 @pytest.fixture(scope="session")
 def table_schema_with_full_nested_fields() -> Schema:
-    return schema.Schema(
+    return Schema(
         NestedField(
             field_id=1,
             name="foo",
@@ -180,7 +179,7 @@ def table_schema_with_full_nested_fields() -> Schema:
 
 @pytest.fixture(scope="session")
 def table_schema_nested() -> Schema:
-    return schema.Schema(
+    return Schema(
         NestedField(field_id=1, name="foo", field_type=StringType(), required=False),
         NestedField(field_id=2, name="bar", field_type=IntegerType(), required=True),
         NestedField(field_id=3, name="baz", field_type=BooleanType(), required=False),
@@ -231,7 +230,7 @@ def table_schema_nested() -> Schema:
 
 @pytest.fixture(scope="session")
 def table_schema_nested_with_struct_key_map() -> Schema:
-    return schema.Schema(
+    return Schema(
         NestedField(field_id=1, name="foo", field_type=StringType(), required=True),
         NestedField(field_id=2, name="bar", field_type=IntegerType(), required=True),
         NestedField(field_id=3, name="baz", field_type=BooleanType(), required=False),
@@ -303,7 +302,7 @@ def table_schema_nested_with_struct_key_map() -> Schema:
 
 @pytest.fixture(scope="session")
 def table_schema_with_all_types() -> Schema:
-    return schema.Schema(
+    return Schema(
         NestedField(field_id=1, name="boolean", field_type=BooleanType(), required=True),
         NestedField(field_id=2, name="integer", field_type=IntegerType(), required=True),
         NestedField(field_id=3, name="long", field_type=LongType(), required=True),