Skip some tests with "readnow" board

This series pointed out a few tests that check that a particular index
is in use.  It seems to me that this does not really make sense when
the "readnow" board is in use, as this actually skips index creation.
The tests do pass today, but by accident.  This patch adds the
appropriate "require" line to the tests in question.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
Acked-By: Simon Marchi <simon.marchi@efficios.com>