fix: compatible with unset configurations (#7402)

diff --git a/backend/helpers/pluginhelper/api/pipeline_plan.go b/backend/helpers/pluginhelper/api/pipeline_plan.go
index 6efafb9..67cd424 100644
--- a/backend/helpers/pluginhelper/api/pipeline_plan.go
+++ b/backend/helpers/pluginhelper/api/pipeline_plan.go
@@ -71,13 +71,15 @@
 		compareName := pluginName + ":" + subtaskMetas[s].Name
 		for _, enableSubtask := range enableSubtasksList {
 			subtaskInfo := strings.Split(enableSubtask, ":")
-			subtaskInfoName := subtaskInfo[0] + ":" + subtaskInfo[1]
-			if len(subtaskInfo) > 2 && (subtaskInfoName == compareName) {
-				v, err := strconv.ParseBool(subtaskInfo[2])
-				if err != nil {
-					break
+			if len(subtaskInfo) > 2 {
+				subtaskInfoName := subtaskInfo[0] + ":" + subtaskInfo[1]
+				if subtaskInfoName == compareName {
+					v, err := strconv.ParseBool(subtaskInfo[2])
+					if err != nil {
+						break
+					}
+					subtaskMetas[s].EnabledByDefault = v
 				}
-				subtaskMetas[s].EnabledByDefault = v
 			}
 		}
 	}