job_specs: 2n-clx reduce number of report coverage tests

job_specs: 2n-clx reduce number of report coverage tests

Remove:
- All vts tests, obsolete use cases.
- dot1q tests apart from dot1q-l2bd, superfluous combinations.
- nat44 -pps tests, replaced by -tput tests.
- nat44 h1-p1-s1 single session tests, unessential combination.
- nat44 h4096-p63-s258048 tests, non-essential scale combination.

Change-Id: I2e2ff96dd727977f55e38f7a388f1afe68096aa9
Signed-off-by: Maciek Konstantynowicz <mkonstan@cisco.com>