build fix

.gitlab-ci.yml

@@ -5,9 +5,10 @@ stages:
 
 .test:
   stage: test
-  script:
+  before_script:
     - pip install --break-system-packages --upgrade Cython setuptools pip coverage nose2
     - pip install --break-system-packages -r requirements.txt
+  script:
     - python setup.py install
     - cd example
     - python setup.py bdist_wheel
@@ -15,10 +16,16 @@ stages:
 test_python35:
   extends: .test
   image: python:3.5
+  before_script:
+    - pip install --upgrade Cython setuptools pip coverage nose2
+    - pip install -r requirements.txt
 
 test_python36:
   extends: .test
   image: python:3.6
+  before_script:
+    - pip install --upgrade Cython setuptools pip coverage nose2
+    - pip install -r requirements.txt
 
 test_python37:
   extends: .test