Make tests less istreambuf_iterator implementation dependent

[Jonathan Wakely]

On 27/09/17 22:16 +0200, François Dumont wrote:
>Hi
>
>Â Â Â  I just committed attached patch as trivial.
>
>Â Â Â  Those tests were highly istreambuf_iterator implementation, it is 
>the result of the call to money_get<>::get which is pointing 
>immediately beyond the last character recognized to quote Standard 
>words.

But according to the standard's specification for istreambuf_iterator
it makes no difference, because both iterators point to the same
streambuf and share the state.