Add new rule for gdbserver port 1234

After Apertis:T5031, the port 1234 has been opened. This test has been failing since then because the rules changed.

test jobs:

• https://lava.collabora.co.uk/scheduler/job/1317816
• https://lava.collabora.co.uk/scheduler/job/1317841

Signed-off-by: Frédéric Dalleau frederic.dalleau@collabora.com