address comments

- revert the changes to grantConnect
- separate the cluster with engine version 1.2 into its separate file which required adopting integ.IntegTest
- refactor integ.cluster.ts to also use integ.IntegTest

packages/@aws-cdk/aws-neptune/lib/cluster.ts

@@ -366,7 +366,7 @@ export abstract class DatabaseClusterBase extends Resource implements IDatabaseC
 
   public grantConnect(grantee: iam.IGrantable): iam.Grant {
     if (this.enableIamAuthentication === false) {
-      throw new Error('Cannot grant when IAM authentication is disabled');
+      throw new Error('Cannot grant connect when IAM authentication is disabled');
     }
 
     this.enableIamAuthentication = true;

packages/@aws-cdk/aws-neptune/package.json

@@ -84,6 +84,7 @@
     "@aws-cdk/assertions": "0.0.0",
     "@aws-cdk/cdk-build-tools": "0.0.0",
     "@aws-cdk/integ-runner": "0.0.0",
+    "@aws-cdk/integ-tests": "0.0.0",
     "@aws-cdk/cfn2ts": "0.0.0",
     "@aws-cdk/pkglint": "0.0.0",
     "@types/jest": "^27.5.2"

packages/@aws-cdk/aws-neptune/test/cluster-ev12.integ.snapshot/ClusterTestDefaultTestDeployAssert6A1BBA9D.assets.json

@@ -0,0 +1,19 @@
+{
+  "version": "21.0.0",
+  "files": {
+    "21fbb51d7b23f6a6c262b46a9caee79d744a3ac019fd45422d988b96d44b2a22": {
+      "source": {
+        "path": "ClusterTestDefaultTestDeployAssert6A1BBA9D.template.json",
+        "packaging": "file"
+      },
+      "destinations": {
+        "current_account-current_region": {
+          "bucketName": "cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}",
+          "objectKey": "21fbb51d7b23f6a6c262b46a9caee79d744a3ac019fd45422d988b96d44b2a22.json",
+          "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-file-publishing-role-${AWS::AccountId}-${AWS::Region}"
+        }
+      }
+    }
+  },
+  "dockerImages": {}
+}

packages/@aws-cdk/aws-neptune/test/cluster-ev12.integ.snapshot/ClusterTestDefaultTestDeployAssert6A1BBA9D.template.json

@@ -0,0 +1,36 @@
+{
+ "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."
+    }
+   ]
+  }
+ }
+}

packages/@aws-cdk/aws-neptune/test/cluster-ev12.integ.snapshot/aws-cdk-neptune-integ.assets.json

@@ -0,0 +1,19 @@
+{
+  "version": "21.0.0",
+  "files": {
+    "06bc77521a70e494cf9fb7d601f5111e19745b0ecde4b6ac42b311f1a19f8328": {
+      "source": {
+        "path": "aws-cdk-neptune-integ.template.json",
+        "packaging": "file"
+      },
+      "destinations": {
+        "current_account-current_region": {
+          "bucketName": "cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}",
+          "objectKey": "06bc77521a70e494cf9fb7d601f5111e19745b0ecde4b6ac42b311f1a19f8328.json",
+          "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-file-publishing-role-${AWS::AccountId}-${AWS::Region}"
+        }
+      }
+    }
+  },
+  "dockerImages": {}
+}