Move 'pip install' to CI

.gitlab-ci.yml

@@ -2,6 +2,7 @@
 create_pdf:
   image: ${CI_REGISTRY_IMAGE}
   script:
+    -  pip install -r requirements.txt
     - python3 example.py
   artifacts:
     paths:

Dockerfile

@@ -5,6 +5,3 @@ WORKDIR /ci
 
 RUN mkdir -p /usr/share/fonts/truetype/opensans
 RUN ln -s /ci/OpenSans.ttf /usr/share/fonts/truetype/opensans/opensans.ttf
-
-# Install matplotlib
-RUN pip install -r requirements.txt