[tracker] next step Kubeflow website model registry section

[tarilabs]

• [ ] add additional diagrams to address this comment and this comment
  • this is being done with https://github.com/kubeflow/website/pull/3828
• [x] https://github.com/kubeflow/website/pull/3740
  • [x] expand on section "installation" to document how to install MR separately from KF (comment)
  • [x] avoid ref to main and use tag (comment) for installation
  • [x] add OWNER file in content/en/docs/components/model-registry (can take [katib file as example]
• [x] add example instructions for dry-run REST API inside of notebook this is being done with https://github.com/kubeflow/website/pull/3788
• [x] consider for "registered model" version in kserve part of tutorial to be consistent or similar to the one from previous steps this is being done with https://github.com/kubeflow/website/pull/3788
• [x] request if it's possible to add (while Alpha, with "alpha" label, with * postfix, ...) a "Model Registry (alpha)" in the KF architecture diagram
  • this is being done by Andrey here: https://github.com/kubeflow/website/pull/3780