[Fix](compile) Fix gcc compile on master (#33864)

This is imported by #33511. wrongly used

ColumnStr<T> ();

which violate C++20 standard(see https://wg21.cmeerw.net/cwg/issue2237) but still supported by clang up until now(see llvm/llvm-project#58112)

be/src/vec/functions/function_variadic_arguments.h

@@ -43,6 +43,7 @@ public:
             res = create_decimal(27, 9, true);
             if (!res) {
                 LOG(FATAL) << "Someting wrong with toDecimalNNOrZero() or toDecimalNNOrNull()";
+                __builtin_unreachable();
             }
         } else
             res = std::make_shared<ToDataType>();