Cleanup ado parameters in oci-image-builder

[dekiel]

https://github.tools.sap/kyma/oci-image-builder/issues/71

The oci-image-builder pipeline was build through Hyperspace portal and was using piper pipeline steps and Hyperspace connected services. Piper steps and connected services were using pipeline parameters and variables to parametrise pipeline behaviour. At present the oci-image-builder does not use piper and connected services. All parameters and variables defined for piper or connected services. It's not known which parameters can be removed if any.

Possible candidates are.

• https://github.tools.sap/kyma/oci-image-builder/blob/main/templates/oci-image-builder.yml#L66-L102
• https://github.tools.sap/kyma/oci-image-builder/blob/main/templates/oci-image-builder.yml#L116

Acceptance Criteria

• [ ] oci-image-builder pipeline parameters and variables used by piper or connected services are deleted.
• [ ] ADO parameters used by pipeline are described in pipeline code.