Address post-review comments for BigQuery samples

Change-Id: I74627bc2744d3b0946d34c1d2a04c424ed708e87

Author: Jon Wayne Parrott

bigquery/cloud-client/snippets.py

@@ -104,6 +104,9 @@ def list_rows(dataset_name, table_name, project=None):
     rows = []
     page_token = None
 
+    # Load at most 25 results. You can change this to `while True` and change
+    # the max_results argument to load more rows from BigQuery, but note
+    # that this can take some time. It's preferred to use a query.
     while len(rows) < 25:
         results, total_rows, page_token = table.fetch_data(
             max_results=25, page_token=page_token)

bigquery/cloud-client/snippets_test.py

@@ -40,7 +40,7 @@ def test_list_datasets(capsys):
 
 
 def test_list_tables(capsys):
-    # Requires teh dataset and table to have been created in the test project.
+    # Requires the dataset and table to have been created in the test project.
     snippets.list_tables(DATASET_ID)
 
     out, _ = capsys.readouterr()