Bump actions/download-artifact from 7 to 8 - #61

Unable to download artifact(s): Artifact not found for name: varcond-script-docs Please ensure that your artifact is not expired and the artifact was uploaded using a compatible version of toolkit/upload-artifact. For more information, visit the GitHub Artifacts FAQ: https://github.com/actions/toolkit/blob/main/packages/artifact/docs/faq.md

Generated key documentation not available; skipping.