Update prep-release reference

[emmanuel-ferdman]

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Description

Small PR - Commit ad6ae34 renamed prep-release.js to be prep-release.mjs. This PR adjusts sources to changes.

Checklist

• I have followed the guidelines in the Contributing document
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[emmanuel-ferdman]

@axosoft-ramint kind reminder to review this small PR

[d13]

Thank you so much for your contribution! Merged with 0f6f6ac