I have motivation to use more recent io.kubernetes client-java 14.0.0 and try to build the project with <k8s.client.version>14.0.0</k8s.client.version> in pom.xml. It failed with following test error:
CustomObjectsApiTest.java:[185,30] method listClusterCustomObject in class io.kubernetes.client.openapi.apis.CustomObjectsApi cannot be applied to given types ...
Such error appears to be superficial as no code in the package is calling listClusterCustomObject any more. So please consider removing such tests as well.