helm - let us overwrite the docker:dind image

[julien-michaud]

https://github.com/actions/actions-runner-controller/blob/master/charts/gha-runner-scale-set/templates/_helpers.tpl#L99

see https://docs.docker.com/docker-hub/usage/

Unauthenticated users: 10 pulls/hour

We would like to pull the dind image from our registry instead of dockerhub otherwise we will get in trouble in April

[julien-michaud]

a pr might already be ready #3851

[szc1wz]

hey @julien-michaud,
In our deployment we achieved this by specifying the template part of the values in the json file and passing it to the helm deployment by --set-json tempate=$(json) and it works perfectly fine for us for a longer time already :)