Allow synchronous installation of Groovy Console

[kwin]

As the groovy console is relying on the OSGi installer to deploy the bundle the according service is only available after a certain delay. That makes it impossible to deploy

1. vault-upgrade-hook
2. groovy-console
3. package leveraging groovy upgrade hook

in the same package.
Maybe some mechanism like https://sling.apache.org/documentation/bundles/installer-provider-installhook.html could be used to be able to deploy those three things in one go.