Update rules_docker to v0.20.0

[mishas]

New version of rules_docker was release, and it has a change that breaks rules_k8s.

[k8s-ci-robot]

Hi @mishas. Thanks for your PR.

I'm waiting for a bazelbuild member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[mishas]

/assign @chizhg

[chizhg]

/ok-to-test
/lgtm
/approve

[mishas]

Hello @chizhg and @fejta ,

I'm not really sure about how the "praw" process works, but from the link in "The pull request process is described here" mentioned above it says that the PR will get automatically merged if all tests pass and the PR has the "LGTM" and "approved" labels.

I'm not sure if it's a bug in the automated system, or is there anything else that needs to be done here?

Thank you.

[mishas]

Hello @chizhg and @fejta ,

Sorry for bugging you again - but this is still approved but not merged :(

Thank you.

[chizhg]

/assign @fejta
Shall we configure Tide for this repo?

[fejta]

We should first move it to oss-prow.knative.dev

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: chizhg, fejta, mishas

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• OWNERS [chizhg,fejta]

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