chore: move bigquery/table.py to bigquery/_operations/table.py (#2423)

Thank you for opening a Pull Request! Before submitting your PR, there
are a few things you can do to make sure it goes smoothly:
- [ ] Make sure to open an issue as a
[bug/issue](https://github.com/googleapis/python-bigquery-dataframes/issues/new/choose)
before writing your code! That way we can discuss the change, evaluate
designs, and agree on the general idea
- [ ] Ensure the tests and linter pass
- [ ] Code coverage does not decrease (if any source code was changed)
- [ ] Appropriate docs were updated (if necessary)

Fixes #<issue_number_goes_here> 🦕

Author: GarrettWu

bigframes/bigquery/__init__.py

@@ -60,7 +60,7 @@
 from bigframes.bigquery._operations.search import create_vector_index, vector_search
 from bigframes.bigquery._operations.sql import sql_scalar
 from bigframes.bigquery._operations.struct import struct
-from bigframes.bigquery.table import create_external_table
+from bigframes.bigquery._operations.table import create_external_table
 from bigframes.core.logging import log_adapter
 
 _functions = [

bigframes/bigquery/table.py bigframes/bigquery/_operations/table.pybigframes/bigquery/table.py renamed to bigframes/bigquery/_operations/table.py

@@ -16,7 +16,7 @@
 
 import pytest
 
-import bigframes.bigquery.table
+import bigframes.bigquery
 import bigframes.core.sql.table
 import bigframes.session
 
@@ -80,9 +80,9 @@ def test_create_external_table_ddl_connection():
     assert sql == expected
 
 
-@mock.patch("bigframes.bigquery.table._get_table_metadata")
+@mock.patch("bigframes.bigquery._operations.table._get_table_metadata")
 def test_create_external_table(get_table_metadata_mock, mock_session):
-    bigframes.bigquery.table.create_external_table(
+    bigframes.bigquery.create_external_table(
         "my-project.my_dataset.my_table",
         columns={"col1": "INT64", "col2": "STRING"},
         options={"format": "CSV", "uris": ["gs://bucket/path*"]},