Bump actions/setup-java from 4.9.1 to 6.0.1 - #3

No file in /home/runner/work/agentspaces-clj/agentspaces-clj matched to [**/pom.xml,**/.mvn/wrapper/maven-wrapper.properties,**/.mvn/extensions.xml], make sure you have checked out the target repository

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@11d5960a326750d5838078e36cf38b85af677262. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/