Fix typo s/with/will/ (#457)

Signed-off-by: David A. Wheeler <[email protected]>

Author: david-a-wheeler

docs/labs/hello.html

@@ -151,7 +151,7 @@ <h2>Task Information</h2>
 <p>
 When you get a correct answer, you'll see a popup notification, the
 background color of the input box will change, and the
-"Interactive Lab" heading with change to say <i>Complete!</i>.
+"Interactive Lab" heading will change to say <i>Complete!</i>.
 
 <p>
 <h2>Interactive Lab (<span id="grade"></span>)</h2>