Changes the name of REQUIRED_OVERRIDE to CUSTOM_SCHEMA_VALUES as that makes a little more sense (it applies to more than required) and removes the ForceNew value since it wasn't hooked up anywhere.

This updates the Dataproc WorkflowTemplate resource, fixing the version field retyping that was otherwise blocking GoogleCloudPlatform/magic-modules#5197. I deprecated it- not sure if it's on the docket for 4.0.0, I haven't rolled it in yet (we already have enough to do)

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dataproc: deprecated the `google_dataproc_workflow_template.version` field, as it wasn't actually useful. The field is used during updates, but updates aren't currently possible with the resource.

Derived from GoogleCloudPlatform/magic-modules#5249