Retarget net40/net451 to net462 - #235

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/upload-artifact@5d5d22a31266ced268874388b861e4b58bb5c2f3. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/