Configured namespaces are not reloaded into main cluster view

[juv]

Describe the bug
Hi, I am currently trying out #702

When I add namespaces in the settings tab and switch back into the main cluster view, I can not see the list of namespaces which I added. Right-clicking the cluster, disconnecting and reconnecting does not fix this issue. What helps is to restart the Lens application entirely.

To Reproduce
Steps to reproduce the behavior:

1. Go to a cluster settings page
2. Add a few namespaces
3. Go back to the main cluster view or disconnect from the cluster and reconnect
4. Configured namespaces are not visible in the drop-down menu
5. Close Lens entirely and restart
6. List of configured namespaces in the main cluster view is now correct

Expected behavior
Namespace list will be updated once the settings are changed

Environment (please complete the following information):

• Lens Version: 4.0.0-alpha5
• OS: [e.g. OSX] Windows 10
• Installation method (e.g. snap or AppImage in Linux): Github binary download

[Nokel81]

Fixed by #2193