[BUG] Operator-examples, example_plot shows empty output pane

[allenleetc]

Describe the problem

Running

Code to reproduce issue

No code necessary, just install operator-examples

System information

• OS Platform and Distribution: Mac M3
• Python version (python --version): 3.9
• FiftyOne version (fiftyone --version): 1.3.0
• FiftyOne installed from (pip or source): pip

Willingness to contribute

The FiftyOne Community encourages bug fix contributions. Would you or another
member of your organization be willing to contribute a fix for this bug to the
FiftyOne codebase?

• Yes. I can contribute a fix for this bug independently
• Yes. I would be willing to contribute a fix for this bug with guidance
  from the FiftyOne community
• No. I cannot contribute a bug fix at this time