fix(e2e): isolate kustomize tests not to interfere with each other

[tadayosi]

What I see as the possible root cause of the random kustomize tests failures is that kustomize taints kustomization.yaml under install/ each test run and it could be that the installation scripts are not idempotent, so the random order of test executions sometimes cause misconfigurations.

This fix copies install/ every time to /tmp and run the tests there to ensure independence of kustomize tests.

Fix #3772 #3861

Release Note

NONE

[tadayosi]

Hmm, while I still believe the fix is a good to have, unfortunately it doesn't seem to solve the original issue completely.
https://github.com/tadayosi/camel-k/actions/runs/3589400137/jobs/6041791903

I'll look into it further...

[tadayosi]

@squakez @phantomjinx I've been doing several things on this pull req, and it seems I finally reached the point where the kustomize tests are actually stabilised.

I've experimented and applied several improvements here, but among those the most contributing change is apparently this: 1bce55b
So surprisingly, what is causing the Kustomize E2E instability seems to be the mixed use of bash and dash in Makefile!

[squakez]

@squakez @phantomjinx I've been doing several things on this pull req, and it seems I finally reached the point where the kustomize tests are actually stabilised.

I've experimented and applied several improvements here, but among those the most contributing change is apparently this: 1bce55b So surprisingly, what is causing the Kustomize E2E instability seems to be the mixed use of bash and dash in Makefile!

Yes, I've noticed in the past that we have mixed scripts with bash or sh. I guess that at some point we should harmonize them as well.