fix(JsonTest): write string hello 断言改用 strcmp（追加14 遗留，i8* == 是指针地址比较）

Test/JsonTest/App/main.vp

@@ -153,7 +153,7 @@ def test_write(pool: memhub.MemPool | t.CPtr):
     # 写字符串
     v2: json.JsonValue | t.CPtr = json.string_val(pool, "hello")
     s2: t.CChar | t.CPtr = json.write(pool, v2, False)
-    testcheck.check(s2 == '"hello"', "write string hello", "write string hello")
+    testcheck.check(string.strcmp(s2, '"hello"') == 0, "write string hello", "write string hello")
 
     # 写布尔
     v3: json.JsonValue | t.CPtr = json.bool_val(pool, True)