Option to specify service account to run Argo workflow

[mocsharp]

Is your feature request related to a problem? Please describe.

The current Argo plugin launches all jobs using the default user which requires the patch pod permission.

Describe the solution you'd like

We shall allow users to specify a service account in the workflow definition as an argument that gets passed to the Argo plugin.

[neildsouth]

I believe this is possible by setting it in the Argo definition workflow.spec.serviceAccountName

re. https://github.com/argoproj/argo-workflows/blob/7abead2a564876a695201cf7539bd20d1fc67888/docs/workflow-rbac.md

[woodheadio]

Moving this to the 0.3.0 milestone as this won't be done for 0.2.0, but as Neil suggests this can be configured in the Argo workflow Template.

We may have a future API call to add a ARGO Workflow template to ARGO, at which time, we will look to investigate this further.