expression: fix the vectorization test framework to produce negative decimal types (#13335)
expression: fix the vectorization test framework to produce negative decimal types (#13335)


kyle-wang/tidb,pingcap/tidb,coocood/tidb,coocood/tidb,ngaut/tidb,ming-relax/tidb,c4pt0r/tidb,pingcap/tidb,ngaut/tidb,kyle-wang/tidb,pingcap/tidb,c4pt0r/tidb,ming-relax/tidb,pingcap/tidb,ngaut/tidb,c4pt0r/tidb,Cofyc/tidb,c4pt0r/tidb,EvilMcJerkface/tidb,c4pt0r/tidb,kyle-wang/tidb,c4pt0r/tidb,ngaut/tidb,ngaut/tidb,Cofyc/tidb,kyle-wang/tidb,pingcap/tidb,ngaut/tidb,EvilMcJerkface/tidb,kyle-wang/tidb,XuHuaiyu/tidb,XuHuaiyu/tidb,kyle-wang/tidb,pingcap/tidb