Hide At Risk section to accomodate claim.

The claim made in the abstract suggests that all features are
implemented, consequently, even features shown with a single implementer
are no longer at risk.

However, this change should be reverted once data can be provided.

Author: BigBlueHat

abstract.hbs

@@ -15,4 +15,15 @@
     a successful implementation of every feature, including the ability to
     host multiple statuses in a single list.
   </p>
+
+  <style>
+    /* The "At Risk" section is currently hidden due to the above claim */
+    .tocxref[href="#At Risk"],
+    section#At\ Risk {
+      display: none;
+    }
+    .at-risk {
+      outline: none;
+    }
+  </style>
 </section>