fix blockCache memory leak
fix blockCache memory leak

currently, the blockCache is used to hold blocks which has not been persisted, once the block persist is complete, it will be deleted from the blockCache, So add a  persisted block into the blockCache, it will not be removed forever, cause memory leak.

Signed-off-by: laizy <8363387fa31f7f7ed66add1276fca560ec754747@onchain.com>

zhouziyan/DNA,BooniesFX/DNA,zhengq1/DNA,qingche123/DNA,BooniesFX/DNA,dreamfly281/DNA,luodanwg/DNA,zhouziyan/DNA,luodanwg/DNA,qingche123/DNA,zhengq1/DNA,dreamfly281/DNA