[java-generator] Default values + x-kubernetes-int-or-string breaks compilation

[andreaTP]

Describe the bug

When a default is provided for a field of type IntOrString the generated code attempts to do a straight assignment to String which is not allowed.

Reported by @kornys

Fabric8 Kubernetes Client version

SNAPSHOT

Steps to reproduce

A field like:

                      pvcSize:
                        anyOf:
                        - type: integer
                        - type: string
                        default: 10Gi
                        description: 'Customize the size of the PVC created for the
                          default MariaDB instance. Default: 10Gi'

breaks compilation.

Expected behavior

Compilation should succeed and the generated code should be immediately usable.

Runtime

other (please specify in additional context)

Kubernetes API Server version

next (development version)

Environment

other (please specify in additional context)

Fabric8 Kubernetes Client Logs

No response

Additional context

No response