Support TFJob v1beta1 crd validation

[Jeffwan]

I am trying to add v1beta1 validation, make schema generation code more generic for all versions.

I am very new to go, I meet issue when I build code. I do think that's the issue from dependency conflicts. Looks like common from tf-operator is not compatible with crd-validation.
Could someone tell me how to make the changes in Gopkg.toml?

# github.com/kubeflow/crd-validation/pkg/crd
pkg/crd/tfjob.go:38:63: cannot use "github.com/kubeflow/tf-operator/pkg/apis/tensorflow/v1beta1".GetOpenAPIDefinitions (type func("github.com/kubeflow/tf-operator/vendor/k8s.io/kube-openapi/pkg/common".ReferenceCallback) map[string]"github.com/kubeflow/tf-operator/vendor/k8s.io/kube-openapi/pkg/common".OpenAPIDefinition) as type func("github.com/kubeflow/crd-validation/vendor/k8s.io/kube-openapi/pkg/common".ReferenceCallback) map[string]"github.com/kubeflow/crd-validation/vendor/k8s.io/kube-openapi/pkg/common".OpenAPIDefinition in argument to utils.GetCustomResourceValidation

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[k8s-ci-robot]

Hi @Jeffwan. Thanks for your PR.

I'm waiting for a kubeflow member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[Jeffwan]

/hold

[Jeffwan]

@gaocegege Hi, could you help take a look at this change?

[gaocegege]

@Jeffwan

Hi, thanks for your contribution. While I think the repo is not ready to produce validation for our API becasue it does not support map. Thus we should wait until k8s supports validation feature for map field.

[Jeffwan]

Thanks. @gaocegege What's your suggestion? Should I close this PR? What I need is the validation process during tfjob creation. Otherwise, it's hard for entry users to detect errors from tfcontroller. Do you have any suggestion?

[gaocegege]

I think we could keep sync with k8s community and wait until k8s supports validation feature for map field. Currently, we have to export errors in the runtime instead of ahead of time. I do not have a better solution.

[Jeffwan]

Thanks @gaocegege I will temporarily leave this PR open and go back to kubernetes side for verification. If k8s has progress on it, we can provide more straightforward messages by enabling map validation