Fix CreateRDSSnapshot function by correct the args and params (#2584)

While refactoring in one of the previous PRs we interchanged two
params of a function and because of that we started getting into
a problem of `DBInstanceIdentifier` not specified.
This commit corrects that.

pkg/function/create_rds_snapshot.go

@@ -139,8 +139,8 @@ func createRDSSnapshot(ctx context.Context, instanceID string, dbEngine RDSDBEng
 	return output, nil
 }
 
-func createSnapshot(ctx context.Context, rdsCli *rds.RDS, snapshotID, dbEngine, instanceID string) (int64, error) {
-	log.WithContext(ctx).Print("Creating RDS snapshot", field.M{"SnapshotID": snapshotID})
+func createSnapshot(ctx context.Context, rdsCli *rds.RDS, snapshotID, instanceID, dbEngine string) (int64, error) {
+	log.WithContext(ctx).Print("Creating RDS snapshot", field.M{"SnapshotID": snapshotID, "InstanceID": instanceID})
 	var allocatedStorage int64
 	if !isAuroraCluster(dbEngine) {
 		dbSnapshotOutput, err := rdsCli.CreateDBSnapshot(ctx, instanceID, snapshotID)