Update 2023-01-17 security post to include GitLab Runner 15.5.2

Why is this change being made?

We released GitLab Runner v15.5.2 to match the GitLab release versions. This merge request updates that.

This merge request also clarifies the helper images update Git for Docker and Kubernetes executors, not the shell or custom executors.

Author Checklist

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• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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