Add the ability for administrators to configure init containers that will run in all workspaces

[dkwon17]

Description

From original issue: https://issues.redhat.com/browse/CRW-9367

As an OpenShift Dev Spaces administrator, I need the ability to inject custom configuration into all Dev Spaces workspaces.

Examples:

• I want to configure a users home directory with custom logic and files.
• I want to extract the OCP CLI from the cluster in order to insure that the oc and kubectl commands in a workspace match the version of the OCP cluster.
• I want to inject custom tools into a workspace

The implementation of this capability could be accomplished via new config options in the CheCluster CR, or via new config options in the DevWorkspaceOperatorConfig

Additional context

[dkwon17]

Fixed thanks to #1532