Reorder the runner Linux installation docs

[christian-stephen]

Description

• Move the step to verify the launch agent service to the end of the section for creating and running the systemd service as it's dependent on it
• Update the relevant systemctl commands that need sudo
• Add a step for starting launch agent while pointing to the optional instructions of running it as a systemd service daemon

Reasons

Jira: N/A

See description above

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