ROENROLL-1858 remove outage banner

src/app/app.component.html

-<div class="alert-banner">
+<!--div class="alert-banner">
   <p><md-icon class="material-icons error" role="img" aria-hidden="true">warning</md-icon> Course Search & Enroll will not be available from June 28 at 4:00pm to July 8 at 8:00am due to the <a href="https://upgrade.sis.wisc.edu/" target="_blank">SIS Upgrade.</a></p>
-</div>
+</div-->
 <header ngClass.sm="hide-navigation-bar" ngClass.xs="hide-navigation-bar" role="banner">
   <cse-header></cse-header>
   <cse-navigation></cse-navigation>