Module Controller should not allow referencing a Test Fragment which holds only pre processor/timer

**orimarko** ([Bug 62074](https://bz.apache.org/bugzilla//show_bug.cgi?id=62074&redirect=false)):
If Test Fragment holds only pre processor/timer, Due to scoping rules, elements won't be executed and therefore it's useless and Module and Include Controller should not allow to add it.

Following a question
https://stackoverflow.com/questions/48078118/test-fragment-not-executing-timers-or-sample-timeout
and related issue 61965

OS: All