Build(deps-dev): Bump sigstore from 4.1.0 to 4.1.1 - #76

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4, rinchsan/renovate-config-validator@v0.2.0. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/