post-rebase placement of Learn LoRaWAN docs in sidebar

Author: jthiller

sidebarsDocs.js

@@ -60,6 +60,13 @@ module.exports = {
             },
           ],
         },
+        {
+          type: 'category',
+          label: 'Learn LoRaWAN',
+          link: { type: 'doc', id: 'network-iot/learn/understanding-lorawan' },
+          items: ['network-iot/learn/understanding-lorawan', 'network-iot/learn/build-a-device'],
+          collapsed: true,
+        },
         {
           type: 'category',
           label: 'Use Helium LoRaWAN',