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Summarize your changes:

Small PR to avoid polluting the global Yarn Berry cache with Verdaccio.

Without this, running npx create-electron-app@alpha with Yarn will generate invalid checksums if you're installing a version number that was previously published to the Verdaccio registry.

This leads to scary errors like:

➤ YN0018: │ @electron-forge/core@npm:8.0.0-alpha.4: The remote archive doesn't match the expected checksum

This PR sets the Yarn cache folders to a subfolder of the Verdaccio STORAGE_PATH, which gets cleaned up at the end of every Verdaccio run.