Upgrade EKS to v18 from v17

Description

This PR upgrades the EKS version for the AWS provider from v17 to v18.

It also includes changes necessary for making the ./tf destroy work without problems. These were caused almost exclusively by namespace dependencies as terraform couldn't infer whether a resource depended on a namespace or not.

Supporting information

• https://tasks.opencraft.com/browse/SE-5536
• https://tasks.opencraft.com/browse/SE-5461
• https://github.com/terraform-aws-modules/terraform-aws-eks/issues/1744

Testing instructions

For SE-5536

• Provision a new AWS cluster. Migrating an existing one won't work.
• There should be no errors.

For SE-5461

• Do the same, but on a ./tf destroy there should be no errors.

Checklist

• All providers include the new feature/change
• All affected providers can provision new clusters
• Unit tests are added/updated
• Documentation is added/updated
• The TOOLS_CONTAINER_IMAGE_VERSION in ci_vars.yml is updated
• The grove-template repository is updated

Other information

• Kubernetes is still on v1.21. v1.23 isn't available yet https://docs.aws.amazon.com/eks/latest/userguide/kubernetes-versions.html
• kubeconfig generation isn't handled by the module anymore, so there's some workarounds to get it back.