iam.api-client.custom_roles_test: test_delete_role failed

[flaky-bot]

Note: #6848 was also for this test, but it was closed more than 10 days ago. So, I didn't mark it flaky.

---

commit: b290e5d
buildURL: Build Status, Sponge
status: failed

Test output

Traceback (most recent call last):
  File "/workspace/iam/api-client/custom_roles_test.py", line 129, in test_delete_role
    CUSTOM_ROLE_STAGE,
  File "/workspace/iam/api-client/custom_roles.py", line 76, in create_role
    'stage': stage
  File "/workspace/iam/api-client/.nox/py-3-7/lib/python3.7/site-packages/googleapiclient/_helpers.py", line 131, in positional_wrapper
    return wrapped(*args, **kwargs)
  File "/workspace/iam/api-client/.nox/py-3-7/lib/python3.7/site-packages/googleapiclient/http.py", line 937, in execute
    raise HttpError(resp, content, uri=self.uri)
googleapiclient.errors.HttpError: 

[flaky-bot]

commit: 0960e02
buildURL: Build Status, Sponge
status: failed

Test output

Traceback (most recent call last):
  File "/workspace/iam/api-client/custom_roles_test.py", line 129, in test_delete_role
    CUSTOM_ROLE_STAGE,
  File "/workspace/iam/api-client/custom_roles.py", line 76, in create_role
    'stage': stage
  File "/workspace/iam/api-client/.nox/py-3-7/lib/python3.7/site-packages/googleapiclient/_helpers.py", line 131, in positional_wrapper
    return wrapped(*args, **kwargs)
  File "/workspace/iam/api-client/.nox/py-3-7/lib/python3.7/site-packages/googleapiclient/http.py", line 937, in execute
    raise HttpError(resp, content, uri=self.uri)
googleapiclient.errors.HttpError: 

[engelke]

Fixed by #9547 and time (for deleted custom roles to age out of using up quota)