Provisioning: Support FolderUid in Dashboard Provisioning Config (#16559)

* add folderUid to DashbaordsAsConfig structs and DashbardProviderConfigs struct, set these values in mapping func
look for new folderUid values in config_reader tests
set dashboard folder Uid explicitly in file_reader, which has no affect when not given

* formatting and docstrings

* add folderUid to DashbaordsAsConfig structs and DashbardProviderConfigs struct, set these values in mapping func
look for new folderUid values in config_reader tests
set dashboard folder Uid explicitly in file_reader, which has no affect when not given

* formatting and docstrings

* add folderUid option, as well as documentation for the rest of the fields

* add blank folderUid in devenv example.

* add folderUid to provisioning sample yaml

* instead of just warning, return error if unmarshalling dashboard provisioning file fails

* Removing the error handling and adding comment

* Add duplicity check for folder Uids


Co-authored-by: swtch1 <joshua.thornton@protonmail.com>

docs/sources/administration/provisioning.md

@@ -203,13 +203,24 @@ The dashboard provider config file looks somewhat like this:
 apiVersion: 1
 
 providers:
+  # <string> provider name
 - name: 'default'
+  # <int> org id. will default to orgId 1 if not specified
   orgId: 1
+  # <string, required> name of the dashboard folder. Required
   folder: ''
+  # <string> folder UID. will be automatically generated if not specified
+  folderUid: ''
+  # <string, required> provider type. Required
   type: file
+  # <bool> disable dashboard deletion
   disableDeletion: false
-  updateIntervalSeconds: 10 #how often Grafana will scan for changed dashboards
+  # <bool> enable dashboard editing
+  editable: true
+  # <int> how often Grafana will scan for changed dashboards
+  updateIntervalSeconds: 10  
   options:
+    # <string, required> path to dashboard files on disk. Required
     path: /var/lib/grafana/dashboards
 ```