LU-4442 test: add version check for replay-vbr.sh test_7g

LU-4442 test: add version check for replay-vbr.sh test_7g

In replay-vbr.sh test_7g.3, because mdt_object_exists() was added
in http://review.whamcloud.com/#/c/8371, client will not be evicted
without object version check.

Test-Parameters: envdefinitions=SLOW=yes,ONLY=7g testlist=replay-vbr
Signed-off-by: Emoly Liu <emoly.liu@intel.com>
Change-Id: Ie3c727aba8bd8bf65460a005412fb217ced341ec
Reviewed-on: http://review.whamcloud.com/8973
Tested-by: Jenkins
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Reviewed-by: Bobi Jam <bobijam@gmail.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>