Harmonize Node.js versions used by CI in all repositories

[marcjansen]

We should use Node.js versions 18.x and 20.x in all repos.

Here are the PRs:

• Use Node.js versions 18.x and 20.x for workflows #2191
• Use Node.js versions 18.x and 20.x for workflows geostyler-openlayers-parser#715
• Use Node.js versions 18.x and 20.x for workflows geostyler-style#580
• Use Node.js versions 18.x and 20.x for workflows geostyler-wfs-parser#517
• Use Node.js versions 18.x and 20.x for workflows geostyler-rest#76
• Use Node.js versions 18.x and 20.x for workflows geostyler-sld-parser#810
• Use Node.js versions 18.x and 20.x for workflows geostyler-shapefile-parser#328
• Use Node.js versions 18.x and 20.x for workflows geostyler-cql-parser#317
• Use Node.js versions 18.x and 20.x for workflows geostyler-qgis-parser#477
• Use Node.js versions 18.x and 20.x for workflows geostyler-data#281
• Use Node.js versions 18.x and 20.x for workflows geostyler-mapfile-parser#250
• Use Node.js versions 18.x and 20.x for workflows (and needed modifications) geostyler-legend#439
• Use Node.js versions 18.x and 20.x for workflows geostyler-cli#351

If this agreed upon, we can merge all these.

Some action runs now produce warnings, as some actions use outdated versions, this will either be fixed in a follow-up or via mend/renovate.

[KaiVolland]

Fails for geostyler-legend. Rest ist merged.

[marcjansen]

Looking into the failing geostyler/geostyler-legend#439

Thanks

[marcjansen]

All in now, closing this discussion.