[MM-37578] - Add setting for onboarding (#18068)

* [MM-37578] - Add setting for onboarding

* fix lint

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

tests/test-config.json

@@ -59,6 +59,7 @@
         "CloseUnusedDirectMessages": false,
         "EnablePreviewFeatures": true,
         "EnableTutorial": true,
+        "EnableOnboardingFlow": true,
         "ExperimentalEnableDefaultChannelLeaveJoinMessages": true,
         "ExperimentalGroupUnreadChannels": "disabled",
         "ImageProxyType": "",