Change Str8Node to use Str8 instead of Str8RO

src/core/strings/str8/str8.h

@@ -21,7 +21,7 @@ typedef const Str8 Str8RO;
 
 typedef struct str8_node Str8Node;
 struct str8_node {
-  Str8RO *string;
+  Str8 *string;
   Str8Node *prev;
   Str8Node *next;
 };