Issue addressed

Fixes #1077

Explanation

I have added the codecov action to one of the tests.yml workflow. The code coverage now succesfully shows here and will also be updated continuously after this PR is merged: https://app.codecov.io/gh/Deltares/hydromt/tree/fix-codecov.

General Checklist

• Updated tests or added new tests >> sort of, updated workflow file
• Branch is up to date with main
• Tests & pre-commit hooks pass
• Updated documentation >> not relevant
• Updated changelog.rst >> not relevant

Data/Catalog checklist

• data/catalogs/predefined_catalogs.yml has not been modified.
• None of the old data_catalog.yml files have been chagned
• data/chagnelog.rst has been updated
• new file uses LF line endings (done automatically if you used update_versions.py)
• New file has been tested locally
• Tests have been added using the new file in the test suite