test: gcc hits constexpr operation limit

Author: PaulXiCao

libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp

@@ -166,12 +166,12 @@ TEST_CONSTEXPR_CXX26 void test()
 
     test_larger_sorts<256>();
     test_larger_sorts<257>();
-    test_larger_sorts<499>();
-    test_larger_sorts<500>();
 #if TEST_STD_VER >= 26
     if !consteval // only runtime tests bc. error: "constexpr evaluation hit maximum step limit"
 #endif
     {
+        test_larger_sorts<499>();
+        test_larger_sorts<500>();
         test_larger_sorts<997>();
         test_larger_sorts<1000>();
         test_larger_sorts<1009>();