feat: add a more robust set of tests

[hanoii]

Adding something more useful in terms of test coverage, for now this adds:

Different drupal version and a smaller set of tests are run by GHA strategy matrix

• a very bear dummy drupal module instead of relying on keycdn
• tests if the module has no composer ddev poseer should still work
• with both d10 and 11 of core supported versions tests that:
  • it installs
  • ddev poser works
  • ddev symlink-project works
  • the core version install is the one specified
  • php tests comamnds are available
  • node commands are available

What I like to add in this initial approach is that eslint and stylelint actually does something, but that can be added later.

~The tests will fail until #81 and #80 are accepted.~ They are in, tests should now be green