Fix typo in zsh cowbuilder config.

.zsh.d/os.d/Debian.zsh

@@ -11,7 +11,7 @@ function cow-dist () {
     command=$1
     shift
     
-    echo cowbuilder $command --configfile ~/.cowbuilder/$dist $@
+    cowbuilder $command --configfile ~/.cowbuilder/$dist $@
     return $?
 }