[dataflow] Add "name" parameter in aggregatedListJobs request

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**Is your feature request related to a problem? Please describe.**
The rest API supports the optional parameter "name" to filter the list of jobs by name. https://cloud.google.com/dataflow/docs/reference/rest/v1b3/projects.jobs/aggregated

We would like to use the @google-cloud/dataflow client API to have this functionality

**Describe the solution you'd like**
Be able to pass in a jobName and receive a list of jobs with this name
**Describe alternatives you've considered**
Using the REST API directly
**Additional context**
Add any other context or screenshots about the feature request here.