job_specs: update 2n-tx2 daily and report

Add newly added spd outbound tests with and without flowcache. These new
test may result in too many mlr tests, so remove the least needed tests,
which are 2m and 1m scale tests. This also unifies which scale tests we
run between af_xdp and dpdk tests.

Also cleanup all 2n-tx2 job specs.

Change-Id: I99bedefcef86f4b921f359f1ebf6c42ebdd8c20f
Signed-off-by: Juraj Linkeš <juraj.linkes@pantheon.tech>