添加测试用命，及 hcl 测试说明文档注释

Author: ivan

tencentcloud/resource_tc_clb_target_group.go

@@ -10,6 +10,19 @@ resource "tencentcloud_clb_target_group" "test"{
 }
 ```
 
+Create target group
+
+```hcl
+resource "tencentcloud_clb_target_group" "test"{
+  target_group_name = "hello1"
+  port = 18082
+  target_group_instances {
+    bind_ip = "10.0.0.4"
+    port = 18080
+  }
+}
+```
+
 Import
 
 CLB target group can be imported using the id, e.g.

tencentcloud/resource_tc_clb_target_group_test.go

@@ -28,6 +28,38 @@ func TestAccTencentCloudClbTargetGroup_basic(t *testing.T) {
 	})
 }
 
+func TestAccTencentCloudClbInstanceTargetGroup(t *testing.T) {
+	t.Parallel()
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckClbInstanceDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccClbInstanceTargetGroup,
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckClbInstanceExists("tencentcloud_clb_instance.target_group"),
+					resource.TestCheckResourceAttr("tencentcloud_clb_instance.target_group", "target_group_name", "tgt_grp_test"),
+					resource.TestCheckResourceAttr("tencentcloud_clb_instance.target_group", "port", "33"),
+					resource.TestCheckResourceAttr("tencentcloud_clb_instance.target_group", "target_group_instances.bind_ip", "10.0.0.4"),
+					resource.TestCheckResourceAttr("tencentcloud_clb_instance.target_group", "target_group_instances.port", "33"),
+				),
+			},
+			{
+				Config: testAccClbInstanceTargetGroupUpdate,
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckClbInstanceExists("tencentcloud_clb_instance.target_group"),
+					resource.TestCheckResourceAttr("tencentcloud_clb_instance.target_group", "target_group_name", "tgt_grp_test"),
+					resource.TestCheckResourceAttr("tencentcloud_clb_instance.target_group", "port", "33"),
+					resource.TestCheckResourceAttr("tencentcloud_clb_instance.target_group", "target_group_instances.bind_ip", "10.0.0.4"),
+					resource.TestCheckResourceAttr("tencentcloud_clb_instance.target_group", "target_group_instances.port", "44"),
+				),
+			},
+		},
+	})
+}
+
 func testAccCheckClbTargetGroupDestroy(s *terraform.State) error {
 	logId := getLogId(contextNil)
 	ctx := context.WithValue(context.TODO(), logIdKey, logId)
@@ -81,3 +113,25 @@ resource "tencentcloud_clb_target_group" "test"{
     target_group_name = "qwe"
 }
 `
+
+const testAccClbInstanceTargetGroup = `
+resource "tencentcloud_clb_instance" "target_group" {
+    target_group_name = "tgt_grp_test"
+    port              = 33
+    target_group_instances {
+      bind_ip = "10.0.0.4"
+      port = 18800
+    }
+}
+`
+
+const testAccClbInstanceTargetGroupUpdate = `
+resource "tencentcloud_clb_instance" "target_group" {
+    target_group_name = "tgt_grp_test"
+    port              = 44
+    target_group_instances {
+      bind_ip = "10.0.0.4"
+      port = 18800
+    }
+}
+`