remove support for v0.x release line

[cjihrig]

This commit disables everything related to the old v0.x release line (the master branch in git). The v0.x git branch and old release artifacts will be left in tact.

Fixes: #2573

[cjihrig]

The whitespace changes in this file were done automatically by my editor.

[brendandburns]

Let's leave codeql and test so that if we get PRs we don't accidentally merge broken, malicious code without CI/CD.

It will only run if people send PRs.

[mstruebing]

Nice LGTM to me but I will leave the final approval to @brendandburns.

Should we update the readme in the master branch with a big note that this is a deprecated branch as well?

[cjihrig]

Should we update the readme in the master branch with a big note that this is a deprecated branch as well?

No strong opinion on that, but it would have to be done as a separate PR.

[brendandburns]

/lgtm
/approve

Thanks for cleaning this up. I'm not sure that we need to modify the master branch. We've already switched the default branch to main so in my opinion master is just another branch like any other.

But if someone wants to send a PR, I'm happy to merge it.

[k8s-ci-robot]

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This pull-request has been approved by: brendandburns, cjihrig

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