Update docs to include export commands (#4697)

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---

#### Does this PR need a docs update or release note?

- [ ] ✅ Yes, it's included
- [ ] 🕐 Yes, but in a later PR
- [x] ⛔ No

#### Type of change

<!--- Please check the type of change your PR introduces: --->
- [ ] 🌻 Feature
- [ ] 🐛 Bugfix
- [x] 🗺️ Documentation
- [ ] 🤖 Supportability/Tests
- [ ] 💻 CI/Deployment
- [ ] 🧹 Tech Debt/Cleanup

#### Issue(s)

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* #<issue>

#### Test Plan

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- [x] 💪 Manual
- [ ] ⚡ Unit test
- [ ] 💚 E2E

website/sidebars.js

@@ -68,7 +68,8 @@ const sidebars = {
             'cli/corso-backup-list-exchange',
             'cli/corso-backup-details-exchange',
             'cli/corso-backup-delete-exchange',
-            'cli/corso-restore-exchange']
+            'cli/corso-restore-exchange',
+            'cli/corso-export-exchange']
         },
         {
           type: 'category',
@@ -82,7 +83,8 @@ const sidebars = {
             'cli/corso-backup-list-groups',
             'cli/corso-backup-details-groups',
             'cli/corso-backup-delete-groups',
-            'cli/corso-restore-groups']
+            'cli/corso-restore-groups',
+            'cli/corso-export-groups']
         },
         {
           type: 'category',