Modernize lessons CI with uvx starterkit-ci and add Dependabot for GitHub Actions#331

jpwgnr wants to merge 2 commits intolhcb:masterlhcb/starterkit-lessons:masterfrom

jpwgnr:jpwgnr/updates_consistent_with_starterkit_cijpwgnr/starterkit-lessons:jpwgnr/updates_consistent_with_starterkit_ciCopy head branch name to clipboard