crushtool: add cli test for off-by-one tries vs retries bug

See bug #7370.  This passes on dumpling and breaks prior to the #7370 fix.

Backport: emperor, dumpling
Signed-off-by: Sage Weil <sage@inktank.com>
(cherry picked from commit ed32c4002fb5cb1dd546331651eaf7de1a017471)