[Security] Update postcss and related npm packages. - #505

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/cache@v4, actions/github-script@v6, actions/setup-go@v5, actions/setup-java@v4, actions/setup-node@v4, actions/setup-python@v5, actions/upload-artifact@v4, pnpm/action-setup@v3, stCarolas/setup-maven@v5. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

Branch update-postcss not found in https://github.com/kiegroup/kogito-apps, falling back to kiegroup/kogito-apps main branch

Branch update-postcss not found in https://github.com/kiegroup/kogito-runtimes, falling back to kiegroup/kogito-runtimes main branch

Branch update-postcss not found in https://github.com/kiegroup/drools, falling back to kiegroup/drools main branch

Restore cache failed: Dependencies file is not found in /home/runner/work/kie-tools/kie-tools. Supported file pattern: go.sum

setup-java v4 is deprecated and will no longer receive updates. Please migrate to actions/setup-java@v5.