BigQuery: Verify/implement list options for dataset and job collections #8685

• Verify that "minCreationTime" and "maxCreationTime" filters are available for users of jobs.list.

• Verify that label filtering (the "filter" param) is available for users of datasets.list

• If there are any tests or samples that blindly iterate across the jobs collection, we should add at least a reasonable minCreationTime filter to reduce test times and demonstrate how to limit results to an expected time window.

An example of the implementations in Java: googleapis/google-cloud-java#5717

cc @tswast