Fully clearing out all deprecated infra dirs

[DXCanas]

Summary

Initially put in place during #5596

The idea being that the CD pipelines wouldn't have to updated on the infra side in coordination with the merge of this PR.

But it didn't work:

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David Cañas  [3:21 PM]
I actually added symlinks specifically to avoid having to do this  

David Cañas  [3:30 PM]
Oh. Just got to look at the error message.The problem here is that it is docker inside of docker and docker does not like sym links

twice

Marcella Maki  [4:14 PM] @david the build failed and I don't know if it's me

Already have image (with digest): gcr.io/cloud-builders/docker
unable to prepare context: unable to evaluate symlinks in Dockerfile path: lstat /workspace/k8s/images/app/docker: no such file or directory

if this is a larger issue it does not need to be remediated right now, it's fine.

David Cañas  [4:24 PM]
I had this lined up yesterday, and then was like "nahhh they're not merging it up yet and I might brake build for any other changes" and then completely forgot when you told me you were merging up

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References

Resolves https://github.com/learningequality/infrastructure/issues/660

Reviewer guidance

Enjoy the red 🤩