docs: remove redundant bigquery_update_table_expiration code sample (#1673)

New version of this sample added in #1457 and migrated to in the docs in internal change 570781706. Co-authored-by: Lingqing Gan <lingqing.gan@gmail.com>

Author: tswast

docs/snippets.py

@@ -203,52 +203,6 @@ def test_update_table_description(client, to_delete):
  # [END bigquery_update_table_description]
 
 
-@pytest.mark.skip(
- reason=(
- "update_table() is flaky "
- "https://github.com/GoogleCloudPlatform/google-cloud-python/issues/5589"
- )
-)
-def test_update_table_expiration(client, to_delete):
- """Update a table's expiration time."""
- dataset_id = "update_table_expiration_dataset_{}".format(_millis())
- table_id = "update_table_expiration_table_{}".format(_millis())
- project = client.project
- dataset_ref = bigquery.DatasetReference(project, dataset_id)
- dataset = bigquery.Dataset(dataset_ref)
- client.create_dataset(dataset)
- to_delete.append(dataset)
-
- table = bigquery.Table(dataset.table(table_id), schema=SCHEMA)
- table = client.create_table(table)
-
- # TODO(thejaredchapman): After code sample has been updated from cloud.google.com delete this.
-
- # [START bigquery_update_table_expiration]
- import datetime
-
- # from google.cloud import bigquery
- # client = bigquery.Client()
- # project = client.project
- # dataset_ref = bigquery.DatasetReference(project, dataset_id)
- # table_ref = dataset_ref.table('my_table')
- # table = client.get_table(table_ref) # API request
-
- assert table.expires is None
-
- # set table to expire 5 days from now
- expiration = datetime.datetime.now(datetime.timezone.utc) + datetime.timedelta(
- days=5
- )
- table.expires = expiration
- table = client.update_table(table, ["expires"]) # API request
-
- # expiration is stored in milliseconds
- margin = datetime.timedelta(microseconds=1000)
- assert expiration - margin <= table.expires <= expiration + margin
- # [END bigquery_update_table_expiration]
-
-
 @pytest.mark.skip(
  reason=(
  "update_table() is flaky "