Actually, the tekton's output do not care what the file extension, all files output belong to type: storage. validate types of outputs should be:

	// PipelineResourceTypeGit indicates that this source is a GitHub repo.
	PipelineResourceTypeGit PipelineResourceType = "git"

	// PipelineResourceTypeStorage indicates that this source is a storage blob resource.
	PipelineResourceTypeStorage PipelineResourceType = "storage"

	// PipelineResourceTypeImage indicates that this source is a docker Image.
	PipelineResourceTypeImage PipelineResourceType = "image"

	// PipelineResourceTypeCluster indicates that this source is a k8s cluster Image.
	PipelineResourceTypeCluster PipelineResourceType = "cluster"

	// PipelineResourceTypePullRequest indicates that this source is a SCM Pull Request.
	PipelineResourceTypePullRequest PipelineResourceType = "pullRequest"

	// PipelineResourceTypeCloudEvent indicates that this source is a cloud event URI
	PipelineResourceTypeCloudEvent PipelineResourceType = "cloudEvent"

	// PipelineResourceTypeGCS is the subtype for the GCSResources, which is backed by a GCS blob/directory.
	PipelineResourceTypeGCS PipelineResourceType = "gcs"