[Dana] Fix comment

Author: kostis

dana/programs-erroneous/strwrite_err.dana

@@ -1,6 +1,6 @@
 (*
   This is the powint program containing a semantic error in a call to
-  the writeString function.  The function expexts a byte[] argunment,
+  the writeString function. This function expects a byte[] argunment,
   not an int type (variable temp below).
 *)