fix: update README for user namespace installation using KF_PROFILE script

[aniketpati1121]

✏️ Summary of Changes

Updated the README to replace the direct kustomize command for creating the user namespace with the recommended KF_PROFILE script approach:

• Added export of KF_PROFILE environment variable.
• Ran ./tests/kubeflow_profile_install.sh to install user namespace.

📦 Dependencies

No external dependencies.

🐛 Related Issues

Fixes #3315 - Kubeflow profile creation error in default KIND configuration.

✅ Contributor Checklist

• Tested changes locally using kustomize and KIND cluster.
• All commits are signed-off to satisfy DCO check.
• Considered community guidelines for documentation changes.

[google-oss-prow]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
Once this PR has been reviewed and has the lgtm label, please assign juliusvonkohout for approval. For more information see the Kubernetes Code Review Process.

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

Details

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

[juliusvonkohout]

why did you create this file?

[aniketpati1121]

Good catch 👍
That file was added unintentionally and is not required.
I’ve removed it in the latest commit.

[juliusvonkohout]

I think the original issue was only a bug of kustomize 5.8.0 instead of 5.7.1 but we should link our tests suite here https://github.com/kubeflow/manifests/blob/master/.github/workflows/full_kubeflow_integration_test.yaml at the beginning of the step by step install and tell people that this workflow is verified on each commit to master. and we can maybe switch all step by step commands to use our scripts that we also use in https://github.com/kubeflow/manifests/blob/master/.github/workflows/full_kubeflow_integration_test.yaml

[juliusvonkohout]

Maybe you are also interested in #3313