Update the journal retry test for new functionality.
Update the journal retry test for new functionality.

Tests that the items are retried in order, and that the retry
interval is honoured.

Signed-off-by: Jon Ludlam <e7e3380887a8f95cc9dc4f0d51dedc7e849a287a@citrix.com>

jonludlam/shared-block-ring,djs55/shared-block-ring