config: add a test for `config.toml.example` (#23766)
config: add a test for `config.toml.example` (#23766)

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