Upgrade GitLab Runner to chart version 0.61.2 and app version 16.8.0

Some problems deploying GitLab Runner to K3s cluster via Helm Chart and Flux V2 reconciliation in a GitOps approach, but mitigated via reverting to prior Helm chart version until fix was available.

v16.8.0 (2024-01-18)
Helm Chart 0.61.1
Helm Chart 0.61.2