Github user zentol commented on the issue:
https://github.com/apache/flink/pull/6116
Well it's not really _their_ hadoop, we explicitly allow and intend users
to set different hadoop version for `flink-shaded-hadoop`. For the default
version in master we're hiding all dependencies, but we don't cover other
versions. This also means that enabling dependency convergence for
flink-shaded-hadoop is effectively really really difficult since it would have
to apply to different versions....---
