runipy | Run IPython notebooks as command-line scripts

Based on your log, you're using the shell executor. This will run commands on your local shell, just like you would yourself. The problem is the runner does not use your OS environment variables, so you need to add your python, git, etc. paths to the runner's path environment variable.

The best way to do this is to configure the path variables explicitly in the environment variable in the [[runners]] section of your runner's config.toml. The config.toml file can either be in /etc/gitlab-runner/, ~/.gitlab-runner or / root. This StackOverflow thread shows how to do this. Please read Advanced Configurations for more info.

If you want to download and use a custom docker image, like python:3.9, you need to use the Docker Executor.