Bump github.com/tektoncd/chains from 0.20.1 to 0.21.0

[dependabot]

Bumps github.com/tektoncd/chains from 0.20.1 to 0.21.0.

Changelog

Sourced from github.com/tektoncd/chains's changelog.

Tekton Chains Releases

Release Frequency

Tekton Chains follows the Tekton community [release policy][release-policy] as follows:

• Versions are numbered according to semantic versioning: vX.Y.Z
• At a minimum four LTS release are produced. Additional releases are produced based on availability of new features to be released
• Four releases a year are chosen for long term support (LTS). All remaining releases are supported for approximately 1 month.
  • The first Tekton Chains LTS release will be v0.13.0 in October 2022

Tekton Chains produces nightly builds, publicly available on gcr.io/tekton-nightly.

Transition Process

Before release v0.13 Tekton Chains has worked on the basis of an undocumented support period, providing patch releases when needed. While transitioning to the new support model, v0.11 and v0.12 will be supported for four months from the initial publishing date.

Release Process

Tekton Chains releases are made of YAML manifests and container images. Manifests are published to cloud object-storage as well as [GitHub][tekton-chains-releases]. Container images are signed by [Sigstore][sigstore] via [Tekton Chains][tekton-chains]; signatures can be verified through the [public key][chains-public-key] hosted by the Tekton Chains project.

Further documentation available:

• The Tekton Chains [release process][tekton-releases-docs]
• [Installing Tekton][tekton-installation]
• Standard for [release notes][release-notes-standards]

Backwards Incompatible Changes

In general we aim for new features to be added in a backwards compatible way, but sometimes we will need to make breaking changes. This policy outlines how we will make and communicate these.

NOTE: Tekton Chains is working towards a formal beta release. Until then, all features are technically considered alpha (though we continue to do our best to retain backwards compatibility).

... (truncated)

Commits

• 9a67b0f PipelineRuns with v2alpha4 to process StepActions (#1118)
• 8e9373e Add new v2alpha4 version for TaskRuns (#1111)
• b1773f8 Deprecate v2alpha1 and v2alpha2 (#1122)
• c17cdfc Set readOnlyRootFilesystem as true in Controller (#1121)
• 2391a43 Configure depguard with "lax" mode (#1119)
• 5c0d83b Bump golang.org/x/net from 0.22.0 to 0.23.0 (#1107)
• fd18dd5 Make chains QPS and Burst configuration consistent (#1100)
• b8fb5f1 Update metrics documentation with the prefix (#1112)
• 5986f44 Move external paramenters and resolved dependencies logic out of v2alpha3 (#1...
• 2b5054e Actually use golangci-lint config. (#1106)
• Additional commits viewable in compare view

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[tekton-robot]

Hi @dependabot[bot]. Thanks for your PR.

I'm waiting for a tektoncd 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.

I understand the commands that are listed here.

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/test-infra repository.

[piyush-garg]

/approve
/lgtm

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: piyush-garg

The full list of commands accepted by this bot can be found here.

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• OWNERS [piyush-garg]

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[piyush-garg]

/test pull-tekton-cli-integration-tests