MB-12537: The Python library for Apache CouchDB is no longer needed

All scripts the previously used the Python library for Apache CouchDB
got removed from testrunner. It's no longer needed.

Change-Id: I957c9f0dc0c18f7f628ae5cfb92d958fb2b59885
Reviewed-on: http://review.couchbase.org/42850
Tested-by: Volker Mische <volker.mische@gmail.com>
Reviewed-by: Ketaki Gangal <ketakigangal@gmail.com>