00example: fixed a harmless typo

The script would work nevertheless (given the feature's included)
but lapses are especially wrong in examples.

features.in/00example/main/scripts.d/89-example

@@ -5,7 +5,7 @@
 # NB: to be executed, it must be marked executable first :)
 
 # let's do something very useful
-echo "$0: WORKDIR=$WORKDIR; directory listig:"
+echo "$0: WORKDIR=$WORKDIR; directory listing:"
 ls -l "$WORKDIR"
 
 # and let's _not_ terminate with non-zero for no real reason;