Confirm whether `slurmd` `node-configured` action requires documentation

[dsloanm]

https://canonical-charmed-hpc.readthedocs-hosted.com/en/latest/howto/setup/deploy-slurm/#set-compute-nodes-to-idle documents using the resume action for slurmctld to bring nodes to IDLE following deployment. However, the nodes retain their "new" status in this case and soon return to DOWN status. This can be confirmed by checking the DownNodes entry in slurm.conf with reason New node.

Instead, running the node-configured action for slurmd bring the node to IDLE as expected and clears the "new status" (but has the drawback of needing run on each new compute node, one at a time).

We should either document the node-configured action or adjust the resume action so it works as documented.

[NucciTheBoss]

We do need to document that the node-configured action must be used, but I would prefer to find an alternative instead to this action as it doesn't scale with larger charm deployments.