Install raven-hydro from official git sources

[Zeitsperre]

Changes

• Added support for Python 3.12 and dropped support for Python3.8.
• Upgraded raven-hydro to v0.3.0 and RavenHydroFramework to v3.8.
• ravenpy now requires xclim >= v0.48.2, xarray >= v2023.11.0, and pandas >= 2.2.0.
• Updated GitHub publishing workflows to use Trusted Publisher for TestPyPI/PyPI releases.
• Added Dependabot to keep dependencies up-to-date.
• Now using step-security/harden-runner action to harden GitHub Actions runners.
• Adjusted GitHub Workflows to test against Python 3.9, 3.10, 3.11, and 3.12.
• Updated the build-system requirements when testing with tox to use newer setuptools and wheel versions when building gdal.
• Adjusted the test_emulators expectations to handle the RavenHydroFramework version-dependent outputs.

[coveralls]

coverage: 81.476% (+0.07%) from 81.404% when pulling b78b44e3f2041b8c5013359a277479129bbc119e on upstream-framework into a8c71c915c201b34b3c0d487fac06c844080eb0e on master.