Replace kaniko based image build tests with moby/buildkit based ones

[oliver-goetz]

How to categorize this PR?

/kind enhancement

What this PR does / why we need it:
kaniko is not maintained anymore, so this PR replaces kaniko with moby/buildkit in all image-build tests.
The functionality of the tests is still the same.

It also removes pull-dependency-watchdog-publish-test-images test which is also using kaniko since it is optional and did never run in the past.

Which issue(s) this PR fixes:
Part of #5484

Special notes for your reviewer:
/cc @LucaBernstein

[LucaBernstein]

Thank you!

[gardener-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: LucaBernstein

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• OWNERS [LucaBernstein]

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[gardener-prow]

LGTM label has been added.

Details

Git tree hash: 41cebf13a793e1765d1492802c73c24d2e12a2c3

[gardener-prow]

@oliver-goetz: Updated the job-config configmap in namespace prow at cluster gardener-prow-trusted using the following files:

• key auditlog-forwarder-test-builds.yaml using file config/jobs/auditlog-forwarder/auditlog-forwarder-test-builds.yaml
• key dependency-watchdog-test-builds.yaml using file config/jobs/dependency-watchdog/dependency-watchdog-test-builds.yaml
• key etcd-druid-test-builds.yaml using file config/jobs/etcd-druid/etcd-druid-test-builds.yaml
• key gardener-etcd-druid-hotfix-v0-33.yaml using file config/jobs/etcd-druid/releases/gardener-etcd-druid-hotfix-v0-33.yaml
• key gardener-etcd-druid-hotfix-v0-34.yaml using file config/jobs/etcd-druid/releases/gardener-etcd-druid-hotfix-v0-34.yaml
• key gardener-etcd-druid-hotfix-v0-35.yaml using file config/jobs/etcd-druid/releases/gardener-etcd-druid-hotfix-v0-35.yaml
• key garden-shoot-trust-configurator-test-builds.yaml using file config/jobs/garden-shoot-trust-configurator/garden-shoot-trust-configurator-test-builds.yaml
• key gardener-discovery-server-test-builds.yaml using file config/jobs/gardener-discovery-server/gardener-discovery-server-test-builds.yaml
• key gardener-extension-registry-cache-test-builds.yaml using file config/jobs/gardener-extension-registry-cache/gardener-extension-registry-cache-test-builds.yaml
• key gardener-extension-shoot-rsyslog-relp-test-builds.yaml using file config/jobs/gardener-extension-shoot-rsyslog-relp/gardener-extension-shoot-rsyslog-relp-test-builds.yaml
• key gardener-test-builds.yaml using file config/jobs/gardener/gardener-test-builds.yaml
• key gardener-gardener-release-v1-134.yaml using file config/jobs/gardener/releases/gardener-gardener-release-v1-134.yaml
• key gardener-gardener-release-v1-135.yaml using file config/jobs/gardener/releases/gardener-gardener-release-v1-135.yaml
• key gardener-gardener-release-v1-136.yaml using file config/jobs/gardener/releases/gardener-gardener-release-v1-136.yaml
• key gardener-gardener-release-v1-137.yaml using file config/jobs/gardener/releases/gardener-gardener-release-v1-137.yaml

Details

In response to this:

How to categorize this PR?

/kind enhancement

What this PR does / why we need it:
kaniko is not maintained anymore, so this PR replaces kaniko with moby/buildkit in all image-build tests.
The functionality of the tests is still the same.

It also removes pull-dependency-watchdog-publish-test-images test which is also using kaniko since it is optional and did never run in the past.

Which issue(s) this PR fixes:
Part of #5484

Special notes for your reviewer:
/cc @LucaBernstein

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.