csharp: Fix enum ser/de using extension class
csharp: Fix enum ser/de using extension class

novifinancial/serde-reflection,novifinancial/serde-reflection,novifinancial/serde-reflection,novifinancial/serde-reflection,novifinancial/serde-reflection,novifinancial/serde-reflection,novifinancial/serde-reflection,novifinancial/serde-reflection,novifinancial/serde-reflection