Move example/osgi to sample repository and make it work

[federicorispo]

I'm proposing a project organization change: move the OSGI example in the sample repository to have all the examples in one place. What do you think about this idea?

As I am new to OSGI containers, I am trying to understand how they work. However, I realized that the example no longer work as expected: I am not receiving the graphql schema from localhost:8181/graphql/schema.json as the documentation suggests (it's possible I've made a mistake). I tried to bump all the dependecy versions (you can find the changes in the wip/bump-osgi-example-deps branch), but although Karaf starts and registers the provider, I'm unable to access the GraphQL endpoint.

Can someone with more OSGI experience try to see if the example works and, if not, investigate the cause of this issue?