refactor: switch CGovernanceObject::cs to Mutex

Author: kwvg

src/governance/object.h

@@ -91,7 +91,7 @@ class CGovernanceObject
 
 public:
     /// critical section to protect the inner data structures
-    mutable RecursiveMutex cs;
+    mutable Mutex cs;
 
 private:
     Governance::Object m_obj;