Add missing omitempty that breaks compatibility

[jlpettersson]

Changes

Adding "omitempty" on the optional description: field in WorkspacePipelineDeclaration, to be compatible with previous versions (v0.10.x).

v1alpha1 is type aliased with v1beta1, but a new optional field is added.

Submitting without "omitempty" will result in an error from the admission webhook:

"webhook.tekton.dev" denied the request: mutation failed: cannot decode incoming new object: json: unknown field: "description"

By adding "omitempty" tag, this field is not sent to the server when empty.

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[tekton-robot]

Hi @jlpettersson. Thanks for your PR.

I'm waiting for a tektoncd 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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[jlpettersson]

@googlebot I signed it!

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[vdemeester]

/ok-to-test
/cc @sbwsg

[vdemeester]

/lgtm

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: sbwsg

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