fix: keep the API: postrender.NewExec and Add NewExecWithArgs
fix: keep the API: postrender.NewExec and Add NewExecWithArgs

Signed-off-by: guofutan <9e00c0dbf3df1e40abfbd089d830595576306955@tencent.com>

helm/helm,helm/helm,bacongobbler/helm,bacongobbler/helm