use pip install

.github/workflows/pages.yml

@@ -13,20 +13,22 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
+env:
+  PY_VER: '3.12'
+
 jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - name: Checkout
-        uses: actions/checkout@v4
+      - uses: actions/checkout@v4
         with:
+          # full history
           fetch-depth: 0
-      - name: Setup micromamba
-        uses: mamba-org/setup-micromamba@v1
+      - uses: actions/setup-python@v4
         with:
-          environment-file: environment.yml
-          cache-environment-key: micromamba-${{ hashFiles('requirements.txt') }}
-          post-cleanup: all
+          python-version: ${{ env.PY_VER }}
+          cache: 'pip'
+      - run: pip install -r requirements.txt
       - name: Setup Pages
         id: pages
         uses: actions/configure-pages@v3
@@ -35,7 +37,6 @@ jobs:
           SITE_URL: ${{ steps.pages.outputs.base_url }}
           REPO_URL: ${{ github.server_url	}}/${{ github.repository }}
           REPO_NAME: ${{ github.repository }}
-        shell: micromamba-shell {0}
         run: mkdocs build
       - name: Upload artifact
         uses: actions/upload-pages-artifact@v2