feat: review datasets creation tests

[b8raoult]

Description

Revisit the way datasets creation is tested with pytest and added a few tests. We can now test some recipes without creating a reference result. Instead we can run other checks (to be written)

The tests will run any YAML recipes in the same directory. Which check to do on the results is described in the very same YAML:

checks:
- variables: [ wdir, ws ]
- dates:
  - 2020-01-01T00:00:00
  - 2020-01-01T12:00:00

What problem does this change solve?

What issue or task does this change relate to?

Additional notes

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