Windows packages was updated to 3.8, fix paths

Author: gonzalocasas

.travis.yml

@@ -12,14 +12,14 @@ matrix:
       env:
         - PATH=/c/Python27:/c/Python27/Scripts:$PATH
         - TRAVIS_PYTHON_VERSION=2.7
-    - name: "Python 3.7: Windows"
+    - name: "Python 3.8: Windows"
       os: windows
       language: shell
       before_install:
         - choco install python3
       env:
-        - PATH=/c/Python37:/c/Python37/Scripts:$PATH
-        - TRAVIS_PYTHON_VERSION=3.7
+        - PATH=/c/Python38:/c/Python38/Scripts:$PATH
+        - TRAVIS_PYTHON_VERSION=3.8
     - name: "Python 3.7: Xenial Linux"
       python: 3.7
       dist: xenial
@@ -32,9 +32,8 @@ matrix:
       env: TRAVIS_PYTHON_VERSION=3.7
 
 install:
-  - python -m ensurepip
-  - python -m pip install cython --install-option="--no-cython-compile"
-  - python -m pip install --no-cache-dir -r requirements-dev.txt
+  - pip install cython --install-option="--no-cython-compile"
+  - pip install --no-cache-dir -r requirements-dev.txt
 
 script:
   - python -c "import compas_fab"