Allow specifying rbac.serviceAccountName and rbac.create: true in the official Helm Chart (AWS EKS related)

Currently, the official GitLab Runner Helm Chart allows setting the Service Account name used by Pods in two ways:

1 - Using

rbac:
  create: true

will create a new Service Account and name it automatically or use .Values.fullnameOverride if set.

2 - Setting

rbac:
  create: false
  serviceAccountName: foo 

will use an existing Service account named foo.

I'd like the chart to create a Service Account, but name it explicitly with serviceAccountName, like so:

rbac:
  create: true
  serviceAccountName: foo 

That's useful for AWS EKS users, as the association between IAM roles and Service Accounts is done via service account names. Example from the docs (note line 13):

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Federated": "arn:aws:iam::${ACCOUNT_ID}:oidc-provider/${OIDC_PROVIDER}"
      },
      "Action": "sts:AssumeRoleWithWebIdentity",
      "Condition": {
        "StringEquals": {
          "${OIDC_PROVIDER}:aud": "sts.amazonaws.com",
          "${OIDC_PROVIDER}:sub": "system:serviceaccount:my-namespace:my-service-account"
        }
      }
    }
  ]
}

Nowadays I use .Values.fullnameOverride, but there's no explicit guarantee it will keep being used for service account names.