Upgrade GitLab Runner to chart version 0.61.2 and app version 16.8.0

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