LU-6455 tests: Re-enable replay-vbr and replay-single tests

LU-6455 tests: Re-enable replay-vbr and replay-single tests

Tests replay-vbr 4i, 4j, 4k and 10b and replay-single test 28
were added to the ALWAYS_EXCEPT list because they were failing
on el7. The issues causing those failures have been fixed and
landed in http://review.whamcloud.com/#/c/14928/ .

The replay-vbr and replay-single tests need to be re-enabled.

Test-Parameters: trivial testlist=replay-vbr,replay-vbr,replay-vbr
Test-Parameters: testlist=replay-single,replay-single,replay-single

Signed-off-by: James Nunez <james.a.nunez@intel.com>
Change-Id: Ic6911849ee96673072e4e1a7abe96706c7c9f87f
Reviewed-on: https://review.whamcloud.com/21565
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Saurabh Tandan <saurabh.tandan@intel.com>
Reviewed-by: Wei Liu <wei3.liu@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>