[CONNECT] Allow use of rbac and service account creation without requiring launcher be enabled

When trying to create a service account using

rbac:
    create: True
    serviceAccount:
        create: True
        name: connect-sa
        annotations:
            eks.amazonaws.com/role-arn: <my-arn-here>

it became clear that we cannot create a service account in this method without enabling launcher because of this line. I am able to work around it thanks to @colearendt by using extraObjects to create the service account, making sure to specify it's name in the rbac values, because it's used later here even though we cannot create that service account that way.

It would be nice if we could support creating the service account without requiring launcher being enabled.

Start with charts/rstudio-connect/templates/rbac.yaml, especially the launcher condition linked in the issue, then inspect charts/rstudio-connect/templates/deployment.yaml to see how the service-account name is consumed. Confirm the chart can create the configured service account and RBAC resources when launcher is disabled, while the deployment still references that account.