0030957: Data Exchange - Assembly item Id should not start with '/' symbol

Fix test case: added parsing of the output of the dump note command

src/XCAFDoc/XCAFDoc_AssemblyItemId.cxx

@@ -119,5 +119,6 @@ XCAFDoc_AssemblyItemId::ToString() const
     aStr += '/';
     aStr += anIt.Value();
   }
+  aStr.Remove(1, 1);
   return aStr;
 }