Exclude test files from rollup

[juliangilbey]

Summary

Proposed changes

This PR brings the following changes:

• Only rollup the run-time files; exclude test files. (Otherwise many errors are produced.)

How to test

Describe the tests that you ran to verify your changes:

1. Run the build
2. Observe that you don't get dozens of warnings about unrecognised functions such as "expect".

Test configuration

• Node.js version (if applicable): 18.12.1

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Checklist

• I have added corresponding labels to this PR (like bug, enhancement...); it's a bug, but I don't know how to add labels
• My commits follow the Conventional Commits 1.0 Guidelines;
• My code follows the style guidelines of this project;
• I have performed a self-review of my own code;
• I have mapped technical debts found on my changes; N/A
• I have made changes to the documentation (if applicable); N/A
• My changes generate no new warnings or errors;

[juliangilbey]

I should have added; this patch was written by Israel Galadima