Improve test description

Author: danog

ext/reflection/tests/ReflectionFiber_notrace_1.phpt

@@ -1,5 +1,5 @@
 --TEST--
-ReflectionFiber should not segfault when inspecting fibers with stack frames before suspend
+ReflectionFiber should not segfault when inspecting fibers with no stack frames before suspend
 --FILE--
 <?php
 $f = new Fiber(Fiber::suspend(...));