fix existing test

Author: devnexen

ext/gmp/tests/gmp_random_bits.phpt

@@ -40,7 +40,7 @@ while (1) {
 
 echo "Done\n";
 ?>
---EXPECT--
-gmp_random_bits(): Argument #1 ($bits) must be greater than or equal to 1
-gmp_random_bits(): Argument #1 ($bits) must be greater than or equal to 1
+--EXPECTF--
+gmp_random_bits(): Argument #1 ($bits) must be between 1 and %d
+gmp_random_bits(): Argument #1 ($bits) must be between 1 and %d
 Done