fix(mail(html)): format links in comment of Calendar invitations

UI/Templates/MailPartViewers/UIxMailPartICalViewer.wox

@@ -276,7 +276,7 @@
             </label>
             <div>
               <md-content>
-                <var:string value="authorativeEvent.comment" const:insertBR="1" />
+                <var:string value="authorativeEvent.comment.stringByDetectingURLs" const:insertBR="1" const:escapeHTML="NO"/>
               </md-content>
             </div>
           </div>

UI/WebServerResources/scss/views/MailerUI.scss

@@ -273,6 +273,9 @@ md-sidenav {
   flex: 0 0 100%;
   max-width: 100%;
   word-break: break-word;
+  md-card-content md-content {
+    background-color: inherit;
+  }
 }
 
 .sg-attachment-name {