types: migrate test-infra to testify for `convert_test.go` (#28202)
types: migrate test-infra to testify for `convert_test.go` (#28202)

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