Synced from eclipse/che issue

https://github.com/eclipse/che/issues/21885

Is your enhancement related to a problem? Please describe

Currently it is not possible to configure the use of the Ephemeral storage strategy as the default storage strategy for Che workspaces through the Che Cluster CR.

Describe the solution you'd like

The Che Cluster CR devEnvironments.storage.pvcStrategy should allow for the ephemeral storage strategy.

The Dashboard already supports reading the configured storage type from the Che Cluster CR, and I believe there is already code in place that would allow support for the ephemeral storage strategy (I may be mistaken however).

Describe alternatives you've considered

Currently, it is only possible to use the ephemeral storage strategy on a per-workspace basis by changing the storage-type settings in the dashboard.

There is no way to set the ephemeral storage strategy to be used by all newly created workspaces.

Release Notes Text

It's now possible to specify ephemeral as the default storage strategy for every workspace through the CheCluster custom resource.