update docs build yml

.github/workflows/docs.yml

@@ -19,7 +19,7 @@ jobs:
               run: |
                   python -m pip install --upgrade pip
                   pip install --user --no-cache-dir Cython
-                  pip install --user -r requirements.txt -r requirements_dev.txt
+                  pip install --user requirements_dev.txt
                   pip install .
             # - name: Discover typos with codespell
             #   run: |