Geo - Rake task to check the health of the secondary node does not mention why it is unhealthy

Summary

The rake task to check the health of the secondary node does not show the reason for the node is unhealthy:

$ sudo gitlab-rake geo:status 

GitLab Version: 12.0.0-ee 
Geo Role: Secondary 
Health Status: Unhealthy 
Repositories: 684/22296/22993 (96%) 
Verified Repositories: 650/22180/22993 (96%) 
Wikis: 22994/22993 (100%) 
Verified Wikis: 22987/22993 (99%) 
LFS Objects: 621/621 (100%) 
Attachments: 31487/31487 (100%) 
CI job artifacts: 755345/755345 (100%) 
Repositories Checked: 0/22993 (0%) 
Sync Settings: Full 
Database replication lag: 0 seconds 
Last event ID seen from primary: 12171429 (less than a minute ago) 
Last event ID processed by cursor: 12171427 (less than a minute ago) 
Last status report was: less than a minute ago

Possible fixes

We should include the GeoNodeStatus#health in the output of the rake task when the secondary node is unhealthy.

/cc @geo-team