Update .gitlab-ci.yml

.gitlab-ci.yml

@@ -2,9 +2,9 @@ image: python:rc-alpine
 #python:alpine
 
 before_script:
-  # forcing version 20.0.1 as 20.0.2 has https://github.com/pypa/pip/issues/7217
+  # forcing pip version 19.3.1 as pip version 20.0 has https://github.com/pypa/pip/issues/7217
   # reset to default "pip install --upgrade pip" when the issue is resolved
-  - pip install --upgrade pip==20.0.1
+  - pip install --upgrade pip==19.3.1
   - pip install markdown
   - pip install Pygments
   - pip install mkdocs