Allow to configure workspaces persistent storage from Eclipse Che CR

Synced from eclipse/che issue

https://github.com/eclipse/che/issues/21405

Is your task related to a problem? Please describe

CheCluster API v2 [1] is going to have the dedicated properties for workspace storage configuration:

devEnvironments:
  storage:
      pvcStrategy: <strategy> // 'per-user' or 'per-workspace'
      perUserStrategyPvcConfig:
        claimSize: <size> // will only be applied for 'per-user'
        storageClass: <classname> // will only be applied for 'per-user'

once specified those properties should be used as defaults for DevWorkspaces creation

[1] https://github.com/eclipse-che/che-operator/pull/1324

Describe the solution you'd like

Configure storage related properties from the Eclipse Che CR

Release Notes Text

Workspaces persistent storage options like the strategy and the size are now configurable using CheCluster CR. It's also possible to set the storage strategy to per-workspace now so that developers will be able to run multiple workspaces concurrently.