Create GitHub Action to build static assets (Webpack/Encore)

[brusch]

Currently updating and building the Webpack build files (located in public/build) is a manual process.
The goal of this task should be, that this process is fully automated using GitHub Actions and runs on a regular basis to also update npm packages to the latest available versions.

• Update dependencies defined in package.json
• Check if there were any changes
• Build Webpack Encore artefacts and update them in Git repository (if there were any changes/updates)
• Tiggers for this workflow: cron (daily at night), on push/PR when any related config is getting changed ( e.g. package.json or webpack.config.js, public/assets/* ....) and manual trigger

[fashxp]

won't do anymore.