Fix build warnings

[lorensr]

Removes these make build lines:

INFO    -  Doc file 'advanced/java-client.md' contains an unrecognized relative link '../subscriptions/#integration-testing-subscriptions', it was left as is. Did you mean
           'subscriptions.md#integration-testing-subscriptions'?
INFO    -  Doc file 'data-loaders.md' contains a link '## Scheduled Data Loaders with Dispatch Predicates', but there is no such anchor on this page.
INFO    -  Doc file 'federation.md' contains a link './advanced/federated-testing.md#Using-the-Entities-Query-Builder-API', but the doc 'advanced/federated-testing.md' does not contain an anchor
           '#Using-the-Entities-Query-Builder-API'.
INFO    -  Doc file 'advanced/file-uploads.md' contains a link '../index.md#adding-the-dgs-framework-dependency', but the doc 'index.md' does not contain an anchor '#adding-the-dgs-framework-dependency'.