[github] Remove numpy from installation step

Author: stephane-caron

.github/workflows/build.yml

@@ -29,7 +29,7 @@ jobs:
             - name: "Install dependencies"
               run: |
                   python -m pip install --upgrade pip
-                  python -m pip install black coverage coveralls flake8 flit mccabe mypy numpy pylint pytest tox tox-gh-actions
+                  python -m pip install black coverage coveralls flake8 flit mccabe mypy pylint pytest tox tox-gh-actions
 
             - name: "Run tox targets for ${{ matrix.python-version }}"
               run: |