CDAP-9476 fix spark streaming in local mode
Spark2 streaming with checkpointing expects the job jar to be in
the same place in between runs, which means we can never delete
the jar. So in local mode, create the job jar in the app temp dir,
but not in the job specific temp dir.
Also some minor fixes to get preview tests to work.
CDAP-9476 create spark2 pipeline jars
Creating spark2 versions of cdap-data-pipeline and cdap-data-streams.
These will be packaged in separate directories within the artifacts
directory, and only one will be picked up as a system artifact at
runtime. The new jars just use the existing source code as source,
with different dependencies.