Remove cleanup

.github/workflows/ci.yml

@@ -18,8 +18,7 @@ jobs:
       - uses: mamba-org/setup-micromamba@v1
         with:
           environment-file: .github/environment.yml
-          cache-environment: true
-          post-cleanup: 'all'
+          init-shell: bash
 
       - name: Install OpenMC
         shell: bash