Provide docs and template to make it easy to use SCIM with Workbench

[tnederlof]

Starting in 2024.04.0 Workbench supports user provisioning via SCIM for certain IdPs. It would be really helpful to users of the helm chart to have a quick way to setup the proper token for this to work + documentation on the steps needed specific to K8s/Helm.

The steps from what I can tell are:

1. In conf.server.rserver.conf add: user-provisioning-enabled: 1
2. Create a Secret containing a token (should give guidance on how to create one)
3. Add the following to values.yaml

   pod:
   env:
   - name: WORKBENCH_USER_SERVICE_AUTH_TOKEN_PATH
     value: "/etc/scim-token/scim_token"
   volumes:
   - name: secret-volume
     secret:
       secretName: scim-token
   volumeMounts:
   - name: secret-volume
     readOnly: true
     mountPath: "/etc/scim-token"

[lachlansimpson]

Seen in support ticket #105647

edit: used successfully in #105647