Update and fix Github Actions cookiecutter template

[ar-jan]

• [x] Update Python and NodeJS versions.
• [x] Specify versions as strings, or Python 3.10 is interpreted as 3.1.

[ar-jan]

Looks like cookiecutter-webapp-deluxe itself has dependencies that don't work on Github Actions (yet)

ERROR: Could not build wheels for backports-zoneinfo, which is required to install pyproject.toml-based projects

A generated project however can be tested with with 3.8-3.10.