no explicit pip commands in Windows, always use pacman

Author: harisont

.github/workflows/build-binary-packages.yml

@@ -195,7 +195,6 @@ jobs:
       shell: msys2 {0}
       run: |
         pacman --noconfirm -S python-pip
-        pip install --upgrade pip
 
     - name: Build Python bindings
       shell: msys2 {0}
@@ -204,7 +203,7 @@ jobs:
         EXTRA_LIB_DIRS: /mingw64/lib
       run: |
         cd src/runtime/python
-        python -m pip install setuptools
+        pacman --noconfirm -S python-setuptools
         python setup.py build
         python setup.py install
         cp /usr/lib/python3.9/site-packages/pgf* /c/tmp-dist/python