ddl: fix gofail data race (#6904)
ddl: fix gofail data race (#6904)


wusphinx/tidb,kyle-wang/tidb,c4pt0r/tidb,c4pt0r/tidb,ngaut/tidb,c4pt0r/tidb,ngaut/tidb,ming-relax/tidb,EvilMcJerkface/tidb,Nify/tidb,c4pt0r/tidb,c4pt0r/tidb,Cofyc/tidb,tiancaiamao/tidb,ming-relax/tidb,cosmtrek/tidb,kyle-wang/tidb,kyle-wang/tidb,Nify/tidb,coocood/tidb,kyle-wang/tidb,kyle-wang/tidb,CodeRushing/tidb,wusphinx/tidb,pingcap/tidb,coocood/tidb,pingcap/tidb,tiancaiamao/tidb,ngaut/tidb,pingcap/tidb,pingcap/tidb,XuHuaiyu/tidb,ngaut/tidb,c4pt0r/tidb,mccxj/tidb,pingcap/tidb,cosmtrek/tidb,CodeRushing/tidb,pingcap/tidb,Cofyc/tidb,mccxj/tidb,XuHuaiyu/tidb,ngaut/tidb,ngaut/tidb,kyle-wang/tidb,qiuyesuifeng/tidb,EvilMcJerkface/tidb,qiuyesuifeng/tidb