Add suggested test case

Co-Authored-By: Jorg Adam Sowa <74921107+jorgsowa@users.noreply.github.com>

Author: LamentXU123

ext/standard/tests/strings/setlocale_null_byte.phpt

@@ -20,6 +20,12 @@ try {
     echo $e->getMessage(), "\n";
 }
 
+try {
+    var_dump(setlocale(LC_ALL, ["invalid", "C\0invalid"]));
+} catch (ValueError $e) {
+    echo $e->getMessage(), "\n";
+}
+
 try {
     var_dump(setlocale(LC_ALL, [], new NullByteStringable()));
 } catch (ValueError $e) {
@@ -29,4 +35,5 @@ try {
 --EXPECT--
 setlocale(): Argument #2 ($locales) must not contain any null bytes
 setlocale(): Argument #2 ($locales) must not contain any null bytes
+setlocale(): Argument #2 ($locales) must not contain any null bytes
 setlocale(): Argument #3 must not contain any null bytes