Update end to end example to use workspaces and results ✨

One thing that is confusing about Pipelines being beta and
PipelineResources not being beta is that many of our examples still use
PipelineResources.

In an effort to provide more examples of the alternatives, this commit
takes our very first pipeline example, which builds and pushes multiple
images, then deploys services that use the new images, and updates it to
use workspaces and results (and - copies of - catalog tasks) instead of
PipelineResources.

And as a bonus, now that we have results, the last deploy step will use
the digest of the previously built image to ensure it actually deploys
the right image!

In the future, we should add final tasks to this pipeline that ensure
the deployment is actually running; the pipelinerun can succeed even
when the images specified are bogus.

I removed the build-push kaniko taskrun example since we'd probably want
to point folks at the kaniko task in the catalog instead.

BONUS: uses volume claim templates as well!! 🎉