fix(tke): [125729244] tencentcloud_kubernetes_scale_worker support UNDERWRITE (#3441)

* add

* add

Author: SevenEarth

.changelog/3441.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+resource/tencentcloud_kubernetes_scale_worker: support `UNDERWRITE` for charge type
+```

tencentcloud/services/tke/resource_tc_kubernetes_cluster_extension.go

@@ -1865,7 +1865,7 @@ func tkeGetCvmRunInstancesPara(dMap map[string]interface{}, meta interface{},
 	if v, ok := dMap["instance_charge_type"]; ok {
 		instanceChargeType := v.(string)
 		request.InstanceChargeType = &instanceChargeType
-		if instanceChargeType == svccvm.CVM_CHARGE_TYPE_PREPAID {
+		if instanceChargeType == svccvm.CVM_CHARGE_TYPE_PREPAID || instanceChargeType == svccvm.CVM_CHARGE_TYPE_UNDERWRITE {
 			request.InstanceChargePrepaid = &cvm.InstanceChargePrepaid{}
 			if period, ok := dMap["instance_charge_type_prepaid_period"]; ok {
 				periodInt64 := int64(period.(int))
@@ -1875,8 +1875,8 @@ func tkeGetCvmRunInstancesPara(dMap map[string]interface{}, meta interface{},
 					instanceChargeType)
 				return
 			}
-			if renewFlag, ok := dMap["instance_charge_type_prepaid_renew_flag"]; ok {
-				request.InstanceChargePrepaid.RenewFlag = helper.String(renewFlag.(string))
+			if renewFlag, ok := dMap["instance_charge_type_prepaid_renew_flag"].(string); ok && renewFlag != "" {
+				request.InstanceChargePrepaid.RenewFlag = helper.String(renewFlag)
 			}
 		}
 	}