Backport PR #11234: Upgrade pip before setuptools for Python compat.

.travis.yml

@@ -13,7 +13,8 b' before_install:'
     - git clone --quiet --depth 1 https://github.com/minrk/travis-wheels travis-wheels
     - 'if [[ $GROUP != js* ]]; then COVERAGE=""; fi'
 install:
-    - pip install "setuptools>=18.5" pip --upgrade
+    - pip install pip --upgrade
+    - pip install "setuptools>=18.5" 
     # Installs PyPy (+ its Numpy). Based on @frol comment at:
     # https://github.com/travis-ci/travis-ci/issues/5027
     - |