Allow specifying mode and owner for mountpoint

[wiktorn]

Allow setting mode and owner in Blueprint

When creating and mounting Filestore or Parallelstore storage, they come with the default root:root ownership and 755 mode on their top directory.

Adding this simplifies administration of the cluster, and provides a way to set the owner and mode for the mount point, so no additional actions are necessary once the cluster is up.

The drawback of this approach is that those commands will be unnecessarily repeated each time, a new instance is spun up.

Submission Checklist

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