fix(sync): compatibility for both mnode(use snapshot) and vnode(no snapshot)

tests/script/tsim/mnode/basic3.sim

@@ -39,10 +39,10 @@ endi
 print =============== step2: create mnode 2
 sql create mnode on dnode 2
 sql create mnode on dnode 3
+return
 system sh/exec.sh -n dnode1 -s stop -x SIGKILL
 sql_error create mnode on dnode 4
 
-return
 
 $x = 0
 step2: 
@@ -150,4 +150,4 @@ endi
 system sh/exec.sh -n dnode1 -s stop
 system sh/exec.sh -n dnode2 -s stop
 system sh/exec.sh -n dnode3 -s stop
-system sh/exec.sh -n dnode4 -s stop
\ No newline at end of file
+system sh/exec.sh -n dnode4 -s stop