chore: run librarian generate for google-cloud-error-reporting (#16775)

Author: jskeet

packages/google-cloud-error-reporting/.repo-metadata.json

@@ -13,4 +13,4 @@
     "product_documentation": "https://cloud.google.com/error-reporting",
     "release_level": "preview",
     "repo": "googleapis/google-cloud-python"
-}
+}

packages/google-cloud-error-reporting/tests/unit/test_client.py

@@ -13,8 +13,8 @@
 # limitations under the License.
 
 
-import unittest
 import os
+import unittest
 
 import mock