distsqlrun: remove redundant Close()
distsqlrun: remove redundant Close()

Close() is already called when timedOut is set.

fixes #13989

paperstreet/cockroach,paperstreet/cockroach,paperstreet/cockroach,paperstreet/cockroach,paperstreet/cockroach,paperstreet/cockroach,paperstreet/cockroach,paperstreet/cockroach