selftests: drv-net: increase timeout

selftests: drv-net: increase timeout

The default timeout is 45 seconds, that's too low for the xdp.py test.

Indeed, this test can take up to 3 minutes with some debug kernel config
on NIPA. Set a timeout to 6 minutes, just to be on the safe side.

Note that the Fixes tag here points to the introduction of the xdp.py
test because I don't know when this test started to take more than 45
seconds. That's OK because a timeout of 6 minutes is not exaggerated.

Fixes: 1cbcb1b28b26 ("selftests: drv-net: Test XDP_PASS/DROP support")
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260710-net-sft-fix-containers-v1-5-a2915c294ef5@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>