t/zbd: add run-tests-against-scsi_debug

t/zbd: add run-tests-against-scsi_debug

The newly added test cases in t/zbd/test-zbd-support 72 and 73 require
error injection feature. They can be run with either null_blk or
scsi_debug, which provides the error injection feature. To run the test
cases easily with scsi_debug, add another script run-tests-against-
scsi_debug. It simply prepares a zoned scsi_debug device and run the two
test cases.

Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/r/20250425052148.126788-9-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>