Update .gitlab-ci.yml

.gitlab-ci.yml

-image: python:rc-alpine
-#python:alpine
+image: python:alpine
+#python:rc-alpine
+#
 
 before_script:
   # 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==19.3.1
+  #- pip install --upgrade pip==19.3.1
+  #
+  - pip install --upgrade pip
   - pip install markdown
   - pip install Pygments
   - pip install mkdocs