Correlations: Add better handling to correlation type and update documentation (#109922)

* Add better type handling when correlation is created from provisioning and fix documentation

* add external example

* change error when deprecated key is used

pkg/services/correlations/database.go

@@ -30,7 +30,7 @@ func (s CorrelationsService) createCorrelation(ctx context.Context, cmd CreateCo
 	if correlation.Config.Type == CorrelationType("query") {
 		correlation.Type = CorrelationType("query")
 	} else if correlation.Config.Type != "" {
-		return correlation, ErrInvalidConfigType
+		return correlation, ErrConfigTypeDeprecated
 	}
 
 	err := s.SQLStore.WithTransactionalDbSession(ctx, func(session *db.Session) error {

pkg/services/correlations/models.go

@@ -20,7 +20,7 @@ var (
 	ErrTransformationRegexReqExp     = errors.New("regex transformations require expression")
 	ErrCorrelationsQuotaFailed       = errors.New("error getting correlations quota")
 	ErrCorrelationsQuotaReached      = errors.New("correlations quota reached")
-	ErrInvalidConfigType             = errors.New("correlation contains non default value in config.type")
+	ErrConfigTypeDeprecated          = errors.New("config.type is deprecated; please move type to be sibling of config")
 )
 
 const (