TestDatasource: Add scenario for generating trace data (#59299)

pkg/tsdb/testdatasource/scenarios.go

@@ -43,6 +43,7 @@ const (
 	rawFrameQuery                     queryType = "raw_frame"
 	csvFileQueryType                  queryType = "csv_file"
 	csvContentQueryType               queryType = "csv_content"
+	traceType                         queryType = "trace"
 )
 
 type queryType string
@@ -218,6 +219,11 @@ Timestamps will line up evenly on timeStepSeconds (For example, 60 seconds means
 		handler: s.handleCsvContentScenario,
 	})
 
+	s.registerScenario(&Scenario{
+		ID:   string(traceType),
+		Name: "Trace",
+	})
+
 	s.queryMux.HandleFunc("", s.handleFallbackScenario)
 }