fix deployments that did not have this value configured at all
by providing a sensible default.

(see OXUI-1015)

during startup the ui-middleware might need some more memory, so we adjust the actual limit to something larger.

Fixes #6

since we don't expect admins to collect metrics for those services,
we provide them with some sensible defaults.

this can not only be handled on ingress level, but we need to mount the
express app also on the app root level. This basically just works out of the
box.