Che Dogfooding instance should install DevWorkspace operator + use single-host

DevWorkspace will be soon the default engine.

It would be really nice if the dogfooding instance was close to what users will have.

So, for example: DevWorkspace operator installed by default (chectl flag or being added as option on che-operator https://github.com/eclipse/che-operator/pull/689 )

And as single-host should be default as well, che-dogfooding should be configured to use single-host strategy