Trace values not displayed in Variable Popover for Temporary Display information fields

[twschiller]

Describe the bug

• Trace values from a previous API call step aren't showing in the popover even though the green checkmark is on the step indicating the step ran successfully
• https://pixiebrix.slack.com/archives/C0436P48QHY/p1712948148687709
• Might be related to either the document builder or that it's a brick in a sub-pipeline?

To Reproduce

Steps to reproduce the behavior:

1. Add an API call brick
2. Add a display temporary information brick
3. Run the mod
4. In the text field for the display, look at the API response variable

Actual behavior

No variables listed

Expected behavior

Additional context

• User was doing the language translation tutorial for the certification
• CWS 1.8.12 MV2