modernise unittesting

.github/workflows/testing.yml

@@ -14,33 +14,16 @@ jobs:
       matrix:
         include:
           - operating-system: ubuntu-latest
-            python-version: 3.9
-            label: linux-64-py-3-9
-            prefix: /usr/share/miniconda3/envs/my-env
+            python-version: 3.11
     steps:
     - uses: actions/checkout@v4
     - name: Setup Mambaforge
-      uses: conda-incubator/setup-miniconda@v3
+      uses: conda-incubator/setup-miniconda@v4
       with:
           python-version: ${{ matrix.python-version }}
-          miniforge-variant: Mambaforge
+          miniforge-version: latest
           channels: conda-forge
-          channel-priority: strict
-          activate-environment: my-env
-          use-mamba: true
-    - name: Set cache date and number
-      run: |
-          echo "DATE=$(date +'%Y%m%d')" >> $GITHUB_ENV
-          cat .github/variables/cache_number.env >> $GITHUB_ENV
-    - uses: actions/cache@v2
-      with:
-          path: ${{ matrix.prefix }}
-          key: ${{ matrix.label }}-conda-${{ hashFiles('environment.yml') }}-${{ env.DATE }}-${{ env.CACHE_NUMBER }}
-      id: cache
-    - name: Update environment
-      run: mamba env update -n my-env -f environment.yml
-      if: steps.cache.outputs.cache-hit != 'true'
-
+          environment-file: environment.yml   
     - name: run tests
       shell: bash -l {0}
       run: |