Update CRD to be forward compatible

[Daniel-Fan]

Add preserve unknown field for CS CR field .spec.services[*]

apiVersion: operator.ibm.com/v3
kind: CommonService
metadata:
  name: common-service
spec:
  license:
    accept: false
  operatorNamespace: cs-condition
  servicesNamespace: cs-condition
  size: starterset
  services:
     - name: ibm-im-operator
       resources:
          - xxxx
       spec:
            xxxx
       ...  # Any arbitrary field

[bitscuit]

/lgtm

[ibm-ci-bot]

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