Resolve "Upgrade Helm Tiller Version Used By GitLab Managed Apps"

What does this MR do?

Every time we install a new cluster application we also upgrade to the latest supported Helm version. Which is now upgrade to 2.11.0. This will allow us to assume that all existing clusters have Tiller 2.11.0 for any apps we want to install.

QA

• Upgrading existing 2.7.2 installations
  1. Checkout master (helm 2.7.2)
  2. Configure cluster and install Tiller, Runner, Prometheus, Ingress
  3. Check tiller version is 2.7.2 by using kubectl get pods --all-namespaces and kubectl describe pod tiller-<blah>
  4. Checkout this branch and restart GDK (helm 2.11.0)
  5. Install JupyterHub
  6. Wait for UI to show "Installed"
  7. Check tiller version is 2.11.0 by using kubectl get pods --all-namespaces and kubectl describe pod tiller-<blah>

What are the relevant issue numbers?

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests added for this feature/bug
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides
• [-] Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.

Closes #49726 (closed)