apparmor: fix rule for /proc/*/task/*/comm

`apparmor-pipewire` test currently fails with following AppArmor audit log:
```
# ====
# profile:/usr/bin/pipewire
# sdmode:REJECTING
# denied_mask:wr
# operation:open
# name:/proc/3070/task/3079/comm
# request_mask:wr
```

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

debian/apparmor.d/usr.bin.pipewire

@@ -26,6 +26,7 @@ profile /usr/bin/pipewire {
   owner @{PROC}/*/stat                         r,
   owner @{PROC}/*/fd/                          r,
   owner @{PROC}/*/fd/*                         r,
+  owner @{PROC}/*/task/*/comm                  rw,
 
   # This seems to be mediated as ptrace(trace), ptrace(traceby).
   ptrace (read),