[UpdateWorkflow] Make login node use head-node-driven orchestration f…

[gmarciani]

This PR depends on aws/aws-parallelcluster-cookbook#3188

Description of changes

Make login node use head-node-driven orchestration for the update workflow.

With this change, login nodes do not depend on cfn-hup/cfn-init anymore and mirror the same update mechanism already adopted for compute nodes. With this change we expect the update workflow to be more resilient.

The changes in this PR mirrors the changes made for compute fleet in the following PRs:

1. Replace cfn-hup on compute nodes with systemd timers to signal updates aws-parallelcluster-cookbook#3070: this is the core change that removes cfn-hup
2. [Scaling] Remove usage of cfn-init in Compute Fleet aws-parallelcluster-cookbook#2875: change in cookbook to remove cfn-init, required by change pasted help documentation into the readme #1
3. [Scaling] Removing usage of cfn-init for compute fleet #6655: change in cli to remove cfn-init, required by change pasted help documentation into the readme #1
4. Remove cfn-hup.log from computefleet cloudwatch agent config aws-parallelcluster-cookbook#3093: minor change related to logs

Tests

• ONGOING test_update_slurm

References

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