CI: Use Miniforge over Mambaforge

Mambaforge is being sunsetted by the end of 2024

Author: gselzer

.github/workflows/build.yml

@@ -90,7 +90,7 @@ jobs:
           # Create env with dev packages
           auto-update-conda: true
           python-version: 3.9
-          miniforge-variant: Mambaforge
+          miniforge-version: latest
           environment-file: dev-environment.yml
           # Activate scyjava-dev environment
           activate-environment: scyjava-dev