Increase depth of json stringify fast path

Source/ThirdParty/Duktape/duktape.c

@@ -10734,7 +10734,7 @@ DUK_INTERNAL_DECL duk_small_int_t duk_unicode_re_is_wordchar(duk_codepoint_t cp)
 
 /* How large a loop detection stack to use for fast path */
 #if defined(DUK_USE_JSON_STRINGIFY_FASTPATH)
-#define DUK_JSON_ENC_LOOPARRAY                32
+#define DUK_JSON_ENC_LOOPARRAY                64
 #endif
 
 /* Encoding state.  Heap object references are all borrowed. */