Installing gcc is necessary I for PyPi deploy I guess

.gitlab-ci.yml

@@ -63,7 +63,8 @@ deploy_pypi:
       # Only do a deploy if it's a version tag.
       - $CI_COMMIT_TAG =~ /^v.*/
   before_script:
-    - 'pip install twine'
+    - apk add gcc
+    - pip install twine
     - './cicd/create-pypirc.sh'
   script:
     # Upload to the test PyPi instance, then upload to the real one.