Website: add JNUC banner to device-management page (#22560)

Closes: https://github.com/fleetdm/fleet/issues/22559

Changes:
-Added a banner to the top of the device management page for JNUC
atendees to book a meeting with the CEO.

website/assets/styles/pages/device-management.less

@@ -39,6 +39,27 @@
   strong {
     color: @core-fleet-black;
   }
+  [purpose='jnuc-banner'] {
+    height: 44px;
+    background-color: #0587FF;
+    p {
+      color: #FFF;
+      font-size: 14px;
+      font-weight: 700;
+      margin-bottom: 0px;
+    }
+    a {
+      color: #FFF;
+      text-decoration-line: underline;
+      text-underline-offset: 2px;
+
+    }
+    img {
+      display: inline;
+      height: 20px;
+      margin-right: 10px;
+    }
+  }
   [purpose='page-container'] {
     padding-left: 64px;
     padding-right: 64px;

website/views/pages/device-management.ejs

@@ -1,4 +1,5 @@
 <div id="device-management-page" v-cloak>
+  <div purpose="jnuc-banner" class="d-flex flex-row align-items-center justify-content-center"><img src="/images/icon-hand-wave-20x20@2x.png" alt="👋"><p>Attending JNUC? <a href="https://calendly.com/d/ckwb-wcp-8fz/meet-with-fleet-ceo" target="_blank">Chat with our CEO</a>.</p></div>
   <div purpose="page-container">
     <div purpose="page-content" class="mx-auto">
       <div purpose="hero">