Fix bigquery load from file sample

Change-Id: I5bcb3d41bed33f638e5dba13da3335adfbdc2ead

Author: Jon Wayne Parrott

samples/snippets/load_data_from_file.py

@@ -44,8 +44,6 @@ def load_data_from_file(dataset_name, table_name, source_file_name):
         job = table.upload_from_file(
             source_file, source_format='text/csv')
 
-    job.begin()
-
     wait_for_job(job)
 
     print('Loaded {} rows into {}:{}.'.format(

samples/snippets/load_data_from_file_test.py

@@ -11,17 +11,12 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import pytest
-
 import load_data_from_file
 
 DATASET_ID = 'test_dataset'
 TABLE_ID = 'test_import_table'
 
 
-@pytest.mark.xfail(
-    strict=True,
-    reason='https://github.com/GoogleCloudPlatform/gcloud-python/issues/2133')
 def test_load_table(resource, capsys):
     data_path = resource('data.csv')