Update object_reference.md (nodejs#827)

kidneysolo · Superlokkus · commit 12ce31d79882 · 2020-11-20T18:11:02.000+01:00
diff --git a/doc/object_reference.md b/doc/object_reference.md
@@ -8,7 +8,7 @@ For more general information on references, please consult [`Napi::Reference`](r
 ```cpp
 #include <napi.h>
 
-using namescape Napi;
+using namespace Napi;
 
 void Init(Env env) {
 
