New Task definition policy: enforce trusted artifacts convention

[zregvart]

We should enforce the trusted artifacts result/parameter naming convention. That is:

Any step utilizing the quay.io/redhat-appstudio/build-trusted-artifacts image should have it's positional arguments in the form of $([params|results].*_ARTIFACT)=<any value>.

This rule should be present in the redhat collection.

[lcarva]

@zregvart, this would be policy rules on the task namespace, correct? Since the image value cannot be obtained reliably from a pod executed by cri-o, we cannot rely on this information from the slsa provenance (release namespace policies).

[zregvart]

Yes, this is about validating the Task definitions not attestations.

[lcarva]

#1014