chore(ga): Cleans up unused package from the runner.

[gounthar]

The docker image building fails because of a full-disk.
With this PR, I propose to clean-up the runner's disk before installing our tools;
Partially fixes #502.

Testing done

https://github.com/jenkins-infra/plugin-modernizer-tool/actions/runs/12528217573

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