Merge branch 'selftests-mlxsw-stabilize-red-tests'

Petr Machata says:

====================
selftests: mlxsw: Stabilize RED tests

Tweak the mlxsw-specific RED selftests to increase stability on
Spectrum-3 and Spectrum-4 machines.
====================

Link: https://patch.msgid.link/cover.1728316370.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>