Remove --kubeconfig mycluster.yaml and use KUBECONFIG instead of moving files

[diegolovison]

Pull Request Template for Kubeflow manifests Issues

• Please include a summary of changes and the related issue.
  Improve docs
• The following checklist will help you to satisfy the requirements.

✏️ A brief description of the changes

I changed the documentation to avoid having extra parameters and moving local files

🐛 If this PR is related to an issue, please put the link of the issue here.

Fixes #2738

✅ Unit Test Checklist

• [ X ] 🛠️ Make sure you have installed kustomize == 5.2.1+
• ✍️ Have you written new tests for your core changes, as applicable?
• 🔄 Have you successfully run existing tests with your changes ?
• 🚀 Have you successfully run existing and new tests with your changes ?

✅ Contributor checklist

• [ X ] All the commits have been signed-off (To pass the DCO check)
• [ X ] Submit the Contributor License Agreements (To pass the cla/google check)

---

You can join the CNCF Slack and access our meetings at the Kubeflow Community website. Our channel on the CNCF Slack is here #kubeflow-platform.

[juliusvonkohout]

/lgtm
/approve

since it is from the documentation lead and not harmful

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: juliusvonkohout

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

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [juliusvonkohout]

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