Prepare v0.3.0 (#34)

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AUTHORS.md! -->
### Pull Request Checklist:
- [ ] This PR addresses an already opened issue (for bug fixes /
features)
    - This PR fixes #xyz
- [ ] Tests for the changes have been added (for bug fixes / features)
- [ ] (If applicable) Documentation has been added / updated (for bug
fixes / features)
- [ ] CHANGES.rst has been updated (with summary of main changes)

### What kind of change does this PR introduce?

* Prepares v0.3.0

### Does this PR introduce a breaking change?

No.

### Other information:

With `setuptools-scm` I gather that we simply need to tag the commit on
merge to the main branch.

AUTHORS.md

@@ -3,3 +3,7 @@
 ### Development Lead
 
 * Trevor James Smith <smith.trevorj@ouranos.ca> [@Zeitsperre](https://github.com/Zeitsperre)
+
+### Co-Developers
+
+* David Huard <huard.david@ouranos.ca> [@huard](https://github.com/huard)

CHANGES.md

@@ -1,6 +1,6 @@
 # Changes
 
-## 0.3.0 (2024--soon)
+## 0.3.0 (2024-03-06)
 
 * Updated the `RavenHydroFramework` to v3.8.
 * `raven-hydro` now builds `RavenHydroFramework` directly from the GitHub official source code base.