When cert-manager create the HTTP01 ACME solver pod, when can specify:

• The image: --acme-http01-solver-image
• The serviceAccount (#Adding a new key acme-http01-solver-service-account to provide a se… #3817): --acme-http01-solver-service-account in the controller, or in the PodTemplate of the issuer.
• The resources

But we can't specify the imagePullSecret to use.

This is an issue for:

• Air gapped environments with private registries
• Docker Hub rate limits for anonymous pulls

It is currently possible to use the serviceAccount with an attached imagePullSecret, but it is not always convenient because it requires to update the serviceAccount of every namespace in the cluster to link the imagePullsecret.

With @primael we propose to add imagePullSecrets to the podTemplate options.

/kind feature