statistics: remove reassignment of Handle.pool in NewHandle (#30675)
statistics: remove reassignment of Handle.pool in NewHandle (#30675)

 
ngaut/tidb,c4pt0r/tidb,pingcap/tidb,ngaut/tidb,c4pt0r/tidb,c4pt0r/tidb,ngaut/tidb,kyle-wang/tidb,kyle-wang/tidb,c4pt0r/tidb,kyle-wang/tidb,pingcap/tidb,ngaut/tidb,ngaut/tidb,ngaut/tidb,pingcap/tidb,kyle-wang/tidb,c4pt0r/tidb,pingcap/tidb,kyle-wang/tidb,c4pt0r/tidb,pingcap/tidb,pingcap/tidb,kyle-wang/tidb