docs(frontend): Added clean up section to openshift docs

[rsun19]

Description of your changes:
There may be a need to delete the kubeflow project from the cluster. I added the command here so people who may not be so familiar with OpenShift would know how.

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• You have signed off your commits
• The title for your pull request (PR) should follow our title convention. Learn more about the pull request title convention used in this repository.

[google-oss-prow]

Hi @rsun19. Thanks for your PR.

I'm waiting for a kubeflow 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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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.

[github-actions]

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[HumairAK]

/lgtm
/approve

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: HumairAK

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• manifests/kustomize/OWNERS [HumairAK]

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[HumairAK]

/hold