fix docker build - #59

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744, reviewdog/action-golangci-lint@f9bba13753278f6a73b27a56a3ffb1bfda90ed71. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/