feat(cloudwatch): add option to show labels on pie chart (aws#34745)

### Issue # (if applicable)

Closes aws#28929

### Reason for this change

Cloudwatch Dashboard console has this option but cdk `GraphWidget` does not

### Description of changes

- adds a new optional boolean parameter  to `GraphWidgetProps`  called `displayLabelsOnChart`
  - naming obtained from description of the option in the AWS Console
- updates aws-cloudwatch README.md with sample usage 

### Describe any new or updated permissions being added

N/A


### Description of how you validated changes

Created new unit and integration test and ran them

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: Kasra-G

packages/@aws-cdk-testing/framework-integ/test/aws-cloudwatch/test/integ.dashboard-with-graphwidget-with-labels-visible.js.snapshot/DashboardWithGraphWidgetWithLabelsVisibleIntegrationTest.assets.json

@@ -0,0 +1,63 @@
+{
+ "Resources": {
+  "DashCCD7F836": {
+   "Type": "AWS::CloudWatch::Dashboard",
+   "Properties": {
+    "DashboardBody": {
+     "Fn::Join": [
+      "",
+      [
+       "{\"widgets\":[{\"type\":\"metric\",\"width\":6,\"height\":6,\"x\":0,\"y\":0,\"properties\":{\"view\":\"pie\",\"title\":\"My fancy graph\",\"region\":\"",
+       {
+        "Ref": "AWS::Region"
+       },
+       "\",\"labels\":{\"visible\":true},\"metrics\":[[\"CDK/Test\",\"Metric\",{\"label\":\"Metric left 1 - p99\",\"stat\":\"p99\"}],[\"CDK/Test\",\"Metric\",{\"label\":\"Metric left 2 - TC_10P_90P\",\"stat\":\"TC(10%:90%)\"}],[\"CDK/Test\",\"Metric\",{\"label\":\"Metric left 3 - TS(5%:95%)\",\"stat\":\"TS(5%:95%)\"}]],\"annotations\":{\"horizontal\":[{\"value\":10,\"label\":\"Left annotation\",\"color\":\"#00ff00\",\"fill\":\"above\",\"visible\":true,\"yAxis\":\"left\"},{\"value\":20,\"label\":\"Right annotation\",\"color\":\"#e30d0d\",\"fill\":\"below\",\"visible\":false,\"yAxis\":\"right\"}],\"vertical\":[{\"value\":\"2023-08-20T00:00:00.000Z\",\"label\":\"Vertical annotation\",\"color\":\"#2556f6\",\"fill\":\"after\",\"visible\":true}]},\"yAxis\":{}}},{\"type\":\"metric\",\"width\":6,\"height\":6,\"x\":6,\"y\":0,\"properties\":{\"view\":\"pie\",\"title\":\"My fancy graph\",\"region\":\"",
+       {
+        "Ref": "AWS::Region"
+       },
+       "\",\"metrics\":[[\"CDK/Test\",\"Metric\",{\"label\":\"Metric left 1 - p99\",\"stat\":\"p99\"}],[\"CDK/Test\",\"Metric\",{\"label\":\"Metric left 2 - TC_10P_90P\",\"stat\":\"TC(10%:90%)\"}],[\"CDK/Test\",\"Metric\",{\"label\":\"Metric left 3 - TS(5%:95%)\",\"stat\":\"TS(5%:95%)\"}]],\"annotations\":{\"horizontal\":[{\"value\":10,\"label\":\"Left annotation\",\"color\":\"#00ff00\",\"fill\":\"above\",\"visible\":true,\"yAxis\":\"left\"},{\"value\":20,\"label\":\"Right annotation\",\"color\":\"#e30d0d\",\"fill\":\"below\",\"visible\":false,\"yAxis\":\"right\"}],\"vertical\":[{\"value\":\"2023-08-20T00:00:00.000Z\",\"label\":\"Vertical annotation\",\"color\":\"#2556f6\",\"fill\":\"after\",\"visible\":true}]},\"yAxis\":{}}},{\"type\":\"metric\",\"width\":6,\"height\":6,\"x\":12,\"y\":0,\"properties\":{\"view\":\"pie\",\"title\":\"My fancy graph\",\"region\":\"",
+       {
+        "Ref": "AWS::Region"
+       },
+       "\",\"metrics\":[[\"CDK/Test\",\"Metric\",{\"label\":\"Metric left 1 - p99\",\"stat\":\"p99\"}],[\"CDK/Test\",\"Metric\",{\"label\":\"Metric left 2 - TC_10P_90P\",\"stat\":\"TC(10%:90%)\"}],[\"CDK/Test\",\"Metric\",{\"label\":\"Metric left 3 - TS(5%:95%)\",\"stat\":\"TS(5%:95%)\"}]],\"annotations\":{\"horizontal\":[{\"value\":10,\"label\":\"Left annotation\",\"color\":\"#00ff00\",\"fill\":\"above\",\"visible\":true,\"yAxis\":\"left\"},{\"value\":20,\"label\":\"Right annotation\",\"color\":\"#e30d0d\",\"fill\":\"below\",\"visible\":false,\"yAxis\":\"right\"}],\"vertical\":[{\"value\":\"2023-08-20T00:00:00.000Z\",\"label\":\"Vertical annotation\",\"color\":\"#2556f6\",\"fill\":\"after\",\"visible\":true}]},\"yAxis\":{}}}]}"
+      ]
+     ]
+    }
+   }
+  }
+ },
+ "Parameters": {
+  "BootstrapVersion": {
+   "Type": "AWS::SSM::Parameter::Value<String>",
+   "Default": "/cdk-bootstrap/hnb659fds/version",
+   "Description": "Version of the CDK Bootstrap resources in this environment, automatically retrieved from SSM Parameter Store. [cdk:skip]"
+  }
+ },
+ "Rules": {
+  "CheckBootstrapVersion": {
+   "Assertions": [
+    {
+     "Assert": {
+      "Fn::Not": [
+       {
+        "Fn::Contains": [
+         [
+          "1",
+          "2",
+          "3",
+          "4",
+          "5"
+         ],
+         {
+          "Ref": "BootstrapVersion"
+         }
+        ]
+       }
+      ]
+     },
+     "AssertDescription": "CDK bootstrap stack version 6 required. Please run 'cdk bootstrap' with a recent version of the CDK CLI."
+    }
+   ]
+  }
+ }
+}