Enable data download in github workflows

Author: msimberg

.github/workflows/icon4py-test-model.yml

@@ -54,8 +54,8 @@ jobs:
         shell: bash
         env:
           NUM_PROCESSES: auto
-          ICON4PY_ENABLE_GRID_DOWNLOAD: false
-          ICON4PY_ENABLE_TESTDATA_DOWNLOAD: false
+          ICON4PY_ENABLE_GRID_DOWNLOAD: true
+          ICON4PY_ENABLE_TESTDATA_DOWNLOAD: true
           PYTEST_ADDOPTS: "--durations=0"
         run: |
           uvx nox -s "test_model-${{matrix.python-version}}(basic, ${{ matrix.component }})" -- --backend=${{ matrix.backend }}
@@ -64,8 +64,8 @@ jobs:
         shell: bash
         env:
           NUM_PROCESSES: auto
-          ICON4PY_ENABLE_GRID_DOWNLOAD: false
-          ICON4PY_ENABLE_TESTDATA_DOWNLOAD: false
+          ICON4PY_ENABLE_GRID_DOWNLOAD: true
+          ICON4PY_ENABLE_TESTDATA_DOWNLOAD: true
           PYTEST_ADDOPTS: "--durations=0"
         run: |
           uvx nox -s "test_model-${{matrix.python-version}}(stencils, ${{ matrix.component }})" -- --backend=${{ matrix.backend }} --grid=icon_regional