Fix syntax of first meta http-equiv in F40

Author: kfranqueiro

techniques/failures/F40.html

@@ -3,7 +3,7 @@
         </h1><section class="meta"><p class="id">ID: F40</p><p class="technology">Technology: failures</p><p class="type">Type: Failure</p></section><section id="applicability"><h2>When to Use</h2>
       <p> All pages</p>
    </section><section id="description"><h2>Description</h2>
-      <p><code>meta http-equiv content="{time} url=..."</code> is often used to
+      <p><code>meta http-equiv="refresh" content="{time}; url=..."</code> is often used to
                         automatically redirect users. When this occurs after a time delay, it is an
                         unexpected change of context that may interrupt the user.</p>
       <p>It is acceptable to use the meta element to create a redirect