Add example of jat__submit()

src/bar/baz-simple/test

@@ -13,5 +13,7 @@ jat__pstarts "verify output"
 jat__pend
 
 jat__pstartc "clean up"
+    jat__submit ls.out
+    jat__submit ls.err
     jat__cmd rm "ls.out" "ls.err"
 jat__pend