LibJS: Fix the return value for TemplateLiteral

This ensures that the bytecode generated for TemplateLiterals returns
the correct value.

Userland/Libraries/LibJS/Bytecode/ASTCodegen.cpp

@@ -649,6 +649,8 @@ void TemplateLiteral::generate_bytecode(Bytecode::Generator& generator) const
             generator.emit<Bytecode::Op::ConcatString>(string_reg);
         }
     }
+
+    generator.emit<Bytecode::Op::Load>(string_reg);
 }
 
 void UpdateExpression::generate_bytecode(Bytecode::Generator& generator) const