Fix querybuf test failure (#9091)
Fix querybuf test failure (#9091)

Fix test failure which introduced by #9003.
The following case will occur when querybuf expansion will allocate memory equal to (16*1024)k.
1) make use ```CFLAGS=-DNO_MALLOC_USABLE_SIZE```.
2) ```malloc``` will not allocate more under ```alpine```.
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