Let Cloud Run Job use `StructuredLogHandler` instead of `ClougLoggingHandler`

[xSAVIKx]

Is your feature request related to a problem? Please describe.
When using Client.get_default_handler CloudLoggingHandler is being used automatically for Cloud Run jobs resource. And while #877 fixes the missing labels we're still gonna be using background transport when simplier stdout is doing just fine.

Describe the solution you'd like
If we modify this check

python-logging/google/cloud/logging_v2/client.py

Line 388 in 6264107

elif monitored_resource.type == _RUN_RESOURCE_TYPE:

and allow _RUN_RESOURCE_TYPE OR _CLOUD_RUN_JOB_RESOURCE_TYPE resource type then a structured log handler is gonna be used automatically which should be a better default.

Describe alternatives you've considered
Meanwhile I am using handler = StructuredLogHandler(project_id=client.project) instead of handler = client.get_default_handler() where client is client = CloudLoggingClient()