Impl insert() in Roles

src/pcd.rs

@@ -654,6 +654,10 @@ impl Roles {
     pub fn iter_mut(&mut self) -> std::collections::btree_map::IterMut<'_, String, RoleDefinition> {
         self.0.iter_mut()
     }
+
+    pub fn insert(&mut self, key: String, value: RoleDefinition) -> Option<RoleDefinition> {
+        self.0.insert(key, value)
+    }
 }
 
 #[cfg(test)]