engine_traits: fix default value for fill cache (#8392)
engine_traits: fix default value for fill cache (#8392)

Signed-off-by: 5kbpers <82ce634e1749ff1c036c2970dd69219ac9501357@pingcap.com>
pingcap/tikv,c4pt0r/tikv,BusyJay/tikv,BusyJay/tikv,pingcap/tikv,BusyJay/tikv,BusyJay/tikv