fix ML example

[mattn]

Fix machinelearning-python-bentoml to work in latest Python and bentoml.

[knative-prow]

Welcome @mattn! It looks like this is your first PR to knative/docs 🎉

[netlify]

✅ Deploy Preview for knative ready!

Built without sensitive environment variables

Name	Link
🔨 Latest commit	5d04482
🔍 Latest deploy log	https://app.netlify.com/sites/knative/deploys/664cc7aaffd2260007b7a2c2
😎 Deploy Preview	https://deploy-preview-5983--knative.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[aliok]

cc @knative/serving-approvers

[github-actions]

This Pull Request is stale because it has been open for 90 days with
no activity. It will automatically close after 30 more days of
inactivity. Reopen with /reopen. Mark as fresh by adding the
comment /remove-lifecycle stale.

[mattn]

/reopen

[knative-prow]

@mattn: Reopened this PR.

In response to this:

/reopen

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-sigs/prow repository.

[knative-prow]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: mattn
Once this PR has been reviewed and has the lgtm label, please assign zainabhusain227 for approval. For more information see the Kubernetes Code Review Process.

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