LU-13485 build: Make parallel tests names unique

LU-13485 build: Make parallel tests names unique

This iteration re-used the serial tests internal name for the
parallel test variant. This name clashing causes builds to fail.

Remedy this by adding a postfix tag the internal unique identifier
of the converted parallel tests.

Test-Parameters: trivial
Signed-off-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Change-Id: Ia39bf2e0004abd10a0c7b146eb2ef1cf62e6d891
Reviewed-on: https://review.whamcloud.com/39161
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Patrick Farrell <farr0186@gmail.com>