Gitlab has functionality to generade badges about build status and coverage percentage.
Is it possible to create custom badge to display Pylint results?
Or just display this
If you don't want to use the README, gitlab pages, anybadge or dropbox you can use https://img.shields.io/badge/lint%20score-$score-blue.svg to 'create' a badge (which is just an URL) and change the badge image URL via the gitlab API.