[Feature Request] Allow `Feature`-s specification for Compute nodes

[efim-a-efim]

In our use case, it would be extremely useful to allow specifying Feature-s for compute nodes in ComputeResource. The specified features list should be merged with the features that ParallelCluster currently generates.

Possible generic use case: Cluster admin can specify features for compute nodes and then either create custom partitions with fetaure-based filters or allow users to filter nodes for their jobs directly by feature.

[efim-a-efim]

I've created PRs that implement this:

• Add support for Feature specification for ComputeResources aws-parallelcluster-cookbook#3020
• Allow Feature specification in compute resources #6962