tests/qdict: check more get_try_int() cases

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Suggested-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20170607163635.17635-42-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
