Pipeline: switched lines in before_script

.gitlab-ci.yml

@@ -34,10 +34,10 @@ cache:
 
 before_script:
   - python --version ; pip --version  # For debugging
+  - pip install virtualenv
   - virtualenv venv
   - source venv/bin/activate
   - pip install --upgrade pip setuptools wheel
-  - pip install virtualenv
 
 stages:          # List of stages for jobs, and their order of execution
   - build