Fix: folderIds=0 at get_all_folder_ids_and_names

[pgillich]

Fixes #125 by simple way.
The folderIds=0 must be replaced to folderIds=null
Issue was intruduced with Grafana 12. Fix is tested with Grafana 11 and 12.

Grafana 12 may use different (version of) CLI parameter parser, which puts the 0 as an item of FolderIds, but the null keeps the FolderIds list empty, see in Grafana source code:

FolderIds []int64 `json:"folderIds"`

https://github.com/grafana/grafana/blob/60df44bb2366fa79808dda46bb2657a2a1646307/pkg/services/dashboards/database/database.go#L921

  if len(query.FolderIds) > 0 {
    filters = append(filters, searchstore.FolderFilter{IDs: query.FolderIds})
  }

[pgillich]

@ZPascal Do you have any idea, why several integration tests were failed with below error message?

Request URL is missing an 'http://' or 'https://' protocol.