Impossible to customize the Kubernete Service Account used by the gitlab-runner pods

Until the Helm chart version 0.52.1 (app version 15.11.1) there was a variable in values.yaml to customize the Kubernetes Service Account used by the Gitlab Runner pods:

## Configuration for the Pods that the runner launches for each new job
##
runners:
  [...]
  ## Service Account to be used for runners
  ##
  # serviceAccountName:

This was removed in this MR and thus it is impossible to customize the k8s SA used by our runners since chart version 0.53.0 and agent version 16.0.0.

We have our runners running in one GKE cluster but managing another cluster. We configure the access via Workload Identity using an annotation added to our customized Kubernetes Service Account. It was working until this was changed. I'm rolling back to the Helm chart 0.52.1, that uses the Gitlab Runner version 0.15.11 instead of 0.16.X due to this.

Can we customize the Kubernetes Service Account for runners in a different way? If not, could you add back that functionality?