fix GetScope attribute of a templated class

example: `ns::klass<t1>::attr`

Author: Vipul-Cariappa

clingwrapper/src/clingwrapper.cxx

@@ -789,9 +789,18 @@ Cppyy::TCppScope_t Cppyy::GetScope(const std::string& name,
 
       if (Cppyy::IsTemplate(scope)) {
         std::vector<Cpp::TemplateArgInfo> templ_params;
-        if (!Cppyy::AppendTypesSlow(params, templ_params))
-          return Cpp::InstantiateTemplate(scope, templ_params.data(),
+        if (!Cppyy::AppendTypesSlow(params, templ_params)) {
+          scope = Cpp::InstantiateTemplate(scope, templ_params.data(),
                                           templ_params.size());
+          if (scope) {
+            if (size_t end = name.rfind('>'); end != std::string::npos) {
+              std::string attribute = name.substr(end + 1);
+              if (attribute.size() > 2) // go past ::
+                 Cppyy::GetScope(attribute.substr(2), scope);
+              return scope;
+            }
+          }
+        }
       }
     }
     return nullptr;