Round sidecar link corners on hover

Author: pastelsky

components/sidecar/sidecar-style.scss

@@ -30,6 +30,8 @@
   }
 
   &:hover {
+    border-top-left-radius: 3px;
+    border-bottom-left-radius: 3px;
     color: getColor(white);
   }
 }