Presubmit failure; cannot import k.libsonnet

[jlewi]

Saw the following presubmit failure in #358

generate objects for namespace : unable to read /src/kubeflow/kubeflow/testing/workflows/environments/kubeflow-presubmit-kubeflow-e2e-358-a3e3ed1-672-27bc/main.jsonnet: RUNTIME ERROR: Couldn't open import "k.libsonnet": No match locally or in the Jsonnet library paths.
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	/src/kubeflow/kubeflow/testing/workflows/components/workflows.jsonnet:3:11-30	thunk <k> from <$>

local k = import "k.libsonnet";

[jlewi]

Looks like we upgraded ks in #434. I suspect #358 just needs to be sync'd to pull in the latest changes to the test.

/assign inc0