Bump conda-incubator/setup-miniconda from 2 to 3

Bumps [conda-incubator/setup-miniconda](https://github.com/conda-incubator/setup-miniconda) from 2 to 3.
- [Release notes](https://github.com/conda-incubator/setup-miniconda/releases)
- [Changelog](https://github.com/conda-incubator/setup-miniconda/blob/main/CHANGELOG.md)
- [Commits](conda-incubator/setup-miniconda@v2...v3)

---
updated-dependencies:
- dependency-name: conda-incubator/setup-miniconda
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/python-tests.yml

@@ -28,7 +28,7 @@ jobs:
 
     # We initiate the environment empty, and check if a key for this environment doesn't already exist in the cache
     - name: Initiate empty environment
-      uses: conda-incubator/setup-miniconda@v2
+      uses: conda-incubator/setup-miniconda@v3
       with:
         miniforge-variant: Mambaforge
         miniforge-version: latest