Always add folderTitle to dashboard object to avoid broken UI card

[Shandur]

If you use folderTitle dashboard selector in annotations, it might break the Dashboards card component with an error identifier folderTitle does not exist. The error happens if there is at least one dashboard in the response without a folderTitle field.

Example of annotation:

metadata:
  annotations:
    grafana/dashboard-selector: folderTitle == 'Cool Folder Title'

Tested it with my project - works nicely!

[Shandur]

@K-Phoen Would appreciate feedback (and merge) from you 🙌

[roman-shandurenko]

@K-Phoen up 👋

[roman-shandurenko]

@kcrabbe up :)