Grab images as part of update e2e test

The other commands seem to use `-template "<value>"` without the `=` and using double quotes.

Also see my comment below on `local` with `$(...)`, so maybe `-template "{{range.Items}}{{.ID}} {{end}}"` would be more consistent here.

Also see my comment below on `local` vs. `$(...)`, so:

```shell
  local pod_id_list
  pod_id_list=($("${KUBECFG}" -template "{{range.Items}}{{.ID}} {{end}}" -l simpleService="${CONTROLLER_NAME}" list pods))
```