Escalator: Add new method to privilege escalate within GUI

Author: https://github.com/ne0ndrag0n
Commit: b4456ecdbb
Pull-request: https://github.com/SerenityOS/serenity/pull/15446
Reviewed-by: https://github.com/ADKaster ✅
Reviewed-by: https://github.com/linusg
Reviewed-by: https://github.com/timschumi ✅

Meta/build-root-filesystem.sh

@@ -97,6 +97,10 @@ if [ -f mnt/bin/pls ]; then
     chown 0:$wheel_gid mnt/bin/pls
     chmod 4750 mnt/bin/pls
 fi
+if [ -f mnt/bin/Escalator ]; then
+    chown 0:$wheel_gid mnt/bin/Escalator
+    chmod 4750 mnt/bin/Escalator
+fi
 if [ -f mnt/bin/utmpupdate ]; then
     chown 0:$utmp_gid mnt/bin/utmpupdate
     chmod 2755 mnt/bin/utmpupdate