[BEAM-374] Enable dependency-plugin and failOnWarning at global level.

[peihe]

Spark dependency fix is included in this PR. This is to remove the beam-examples dependency from Spark.
failOnWarning is disabled for Flink for now.

The added dependencies in this PR come from "mvn dependency:analyze"

[peihe]

R: @amitsela for checking the correctness of the spark dependency.
R: @dhalperi for checking IO.
R: @mxm for flink
R: @davorbonaci for the overall PR

[dhalperi]

version numbers should be inherited from root-level pom, I think. See grpc above, for instance.

[peihe]

done

[amitsela]

Added comments, mainly relating to @dhalperi comment on inheriting versions for root level pom (and some suggestions for additional once for Spark's pom).
BTW, is there an additional benefit here ? besides clarity of course. I'm not familiar with analyze-only.

And how does this relate to removing beam-examples dependencies ? Why do we want to remove this dependency ? I would prefer a dependency to use beam-examples in the runner's tests on duplicating them.

[peihe]

Users should be able to run beam-examples with any runners, and beam-examples will need runtime dependency to runners-spark. I cannot add that runtime dependency when runners-spark depends on beam-examples.

Previously, runners-spark is pull dependency from other module, and runners-spark can be broken by dependency changes in other module (removing, changing version, and even adding). This is another benefits.

[amitsela]

Makes sense. Thanks for clarifying that!
LGTM.

[dhalperi]

comment should move.

[peihe]

done

[peihe]

@dhalperi PTAL, and merge if it looks good.

Thanks

[davorbonaci]

LGTM.