Pass service account name in argo workflows

[jrtcppv]

When algorithm workflows are launched from Tator, the field workflow.spec.serviceAccountName should be specified in the workflow definition. This should be added to JobCluster database objects as an optional field. If the value is not defined in the JobCluster, a value of default should be used explicitly. Right now by not specifying this, Argo will use the default account always, which can be problematic in Kube clusters with shared uses.