Typo correction.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@276359 13f79535-47bb-0310-9956-ffa450edef68

docs/manual/CoreTasks/macrodef.html

@@ -272,7 +272,7 @@
 </pre>
     </blockquote>
     <p>
-      The following uses a prior defined attribut for setting the
+      The following uses a prior defined attribute for setting the
       default value of another. The output would be
       <tt>one=test two=test</tt>. If you change the order of lines
       *1 and *2 the output would be <tt>one=test two=@{one}</tt>,