Fix dud alias. Switch --max-depth for just -d

As far as I can tell (tested on Linux & Darwin, BSD man page seems to agree), `-d` is pretty univerally accepted as the depth argument.  So instead of doing a test, we can just use -d and call it a day.

plugins/common-aliases/common-aliases.plugin.zsh

@@ -38,7 +38,7 @@ alias -g NE="2> /dev/null"
 alias -g NUL="> /dev/null 2>&1"
 alias -g P="2>&1| pygmentize -l pytb"
 
-alias dud='du --max-depth=1 -h'
+alias dud='du -d 1 -h'
 alias duf='du -sh *'
 alias fd='find . -type d -name'
 alias ff='find . -type f -name'