New method setup_retentions

[shartgring]

Issue addressed

Fixes #144

Explanation

A new method to include retention basins. Copied from Santa Cruz branch.

Checklist

• [X] Updated tests or added new tests
• [X] Branch is up to date with main
• [X] Tests & pre-commit hooks pass
• [ ] Updated documentation if needed <-- no yet included in example models, only in docstrings
• [X] Updated changelog.rst if needed

Additional Notes (optional)

Only the code itself is copied from Santa Cruz branch and a basic test is added. What still needs to be done is validating whether the created model can run in Delft3D-FM.

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud