CBQE-869 fix a bug when reconstruct cbtransfer automation

Change-Id: I497c630304491a4fe4fbce94ad773893e7382252
Reviewed-on: http://review.couchbase.org/27201
Reviewed-by: Chisheng Hong <chisheng@couchbase.com>
Tested-by: Chisheng Hong <chisheng@couchbase.com>