molecule CI: run multiple scenarios for playbook tests

[dometto]

It is sometimes desirable to run tests for playbooks with multiple scenarios. For roles this is easily achieved by having multiple scenario directories in the role's molecule directory. However, our playbook tests are all in the molecule directory in the repo's root, and are run when the playbook is modified.

There are playbooks for which we have different scenario's:

• molecule/playbook-openrefine
• molecule/playbook-openrefine-standalone

These different scenario's can be run manually, but in CI, only the one corresponding exactly to the playbook name (e.g. playbook-openrefine) will be run at the moment.

Improve the GitHub workflow to test also playbook-openrefine-*.