Fix AppArmor rules for recent Wireplumber

`apparmor-pipewire` test currently fails with following AppArmor audit log:
```
# ====
# profile:/usr/bin/wireplumber
# sdmode:REJECTING
# denied_mask:wr
# operation:open
# name:/proc/1266/task/1272/comm
# request_mask:wr
# ====
# profile:/usr/bin/wireplumber
# sdmode:REJECTING
# denied_mask:wr
# operation:open
# name:/proc/1280/task/1286/comm
# request_mask:wr
```

Signed-off-by: Dylan Aïssi <dylan.aissi@collabora.com>