update docker-in-docker testimage for s390x

[Basavaraju-G]

Changes

#7496 This PR is updated the docker:dind image in the test examples. this is not multi arch image, its failing in s390x CI platforms, so use different image for s390x platform.

CI Failure:
https://dashboard.dogfooding.tekton.dev/#/namespaces/bastion-z/pipelineruns/tekton-pipeline-s390x-nightly-run-mnhzc?pipelineTask=examples-test-pipeline

Submitter Checklist

As the author of this PR, please check off the items in this checklist:

• Has Docs if any changes are user facing, including updates to minimum requirements e.g. Kubernetes version bumps
• Has Tests included if any functionality added or changed
• Follows the commit message standard
• Meets the Tekton contributor standards (including functionality, content, code)
• Has a kind label. You can add one by adding a comment on this PR that contains /kind <type>. Valid types are bug, cleanup, design, documentation, feature, flake, misc, question, tep
• Release notes block below has been updated with any user facing changes (API changes, bug fixes, changes requiring upgrade notices or deprecation warnings). See some examples of good release notes.
• Release notes contains the string "action required" if the change requires additional action from users switching to the new release

Release Notes

NONE

[tekton-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
To complete the pull request process, please assign abayer after the PR has been reviewed.
You can assign the PR to them by writing /assign @abayer in a comment when ready.

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

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[Basavaraju-G]

/kind bug

[Basavaraju-G]

/test pull-tekton-pipeline-build-tests

[khrm]

/test pull-tekton-pipeline-build-tests

[tekton-robot]

@Basavaraju-G: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-tekton-pipeline-build-tests	ebe81d2	link	true	/test pull-tekton-pipeline-build-tests

Full PR test history. Your PR dashboard.

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. I understand the commands that are listed here.

[khrm]

You need to fix formatting with gofmt. https://prow.tekton.dev/view/gs/tekton-prow/pr-logs/pull/tektoncd_pipeline/7600/pull-tekton-pipeline-build-tests/1749843714966032384