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

**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 https://github.com/googleapis/python-logging/pull/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 https://github.com/googleapis/python-logging/blob/62641075042a3da9bb9c059d963bad14a1586b1c/google/cloud/logging_v2/client.py#L388 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()`