CHANGELOG: add changelog for v2.1.2 (#8767) (#8773)
CHANGELOG: add changelog for v2.1.2 (#8767) (#8773)


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