once the lazy loaded services has been loaded, use that instead of the proxy for future container get calls

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes (well more a performance enhancement
| BC breaks?    | no
| Deprecations? | -
| Tests pass?   | -
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Result of a discussion at DrupalCamp Vienna

/cc @dawehner