fix(vpc-v2): fixing default scope id (#31102)

### Issue # (if applicable)

Closes .

### Reason for this change

Fix current default scope ids for IPAM.

### Description of changes

Fix current default scope ids for IPAM..

### Description of how you validated changes

Integration test deployment

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

packages/@aws-cdk/aws-ec2-alpha/lib/ipam.ts

@@ -415,6 +415,11 @@ class IpamScopeBase implements IIpamScopeBase {
  readonly scopeType?: IpamScopeType,
  ) {
  this.scopeType = IpamScopeType.DEFAULT;
+ if (!props.ipamScopeId) {
+ throw new Error('ipamScopeId is required');
+ } else {
+ this.scopeId = props.ipamScopeId;
+ }
  }
 
  /**

packages/@aws-cdk/aws-ec2-alpha/test/integ.subnet-v2.js.snapshot/aws-cdk-vpcv2-alpha-new.template.json

@@ -15,7 +15,12 @@
  "Properties": {
  "AddressFamily": "ipv6",
  "AwsService": "ec2",
- "IpamScopeId": "DefaultPublicScope",
+ "IpamScopeId": {
+ "Fn::GetAtt": [
+ "Ipam50346F82",
+ "PublicDefaultScopeId"
+ ]
+ },
  "Locale": "eu-west-2",
  "PublicIpSource": "amazon"
  }

packages/@aws-cdk/aws-ec2-alpha/test/integ.subnet-v2.ts

@@ -11,7 +11,6 @@
 import * as vpc_v2 from '../lib/vpc-v2';
 import * as ec2 from 'aws-cdk-lib/aws-ec2';
 import { AddressFamily, AwsServiceName, IpCidr, Ipam, IpamPoolPublicIpSource, SubnetV2 } from '../lib';
-//import { Ipv6Cidr } from '../lib';
 import { IntegTest } from '@aws-cdk/integ-tests-alpha';
 import * as cdk from 'aws-cdk-lib';
 import { SubnetType } from 'aws-cdk-lib/aws-ec2';

packages/@aws-cdk/aws-ec2-alpha/test/integ.vpc-v2-alpha.js.snapshot/aws-cdk-vpcv2-alpha.template.json

@@ -14,7 +14,12 @@
  "Type": "AWS::EC2::IPAMPool",
  "Properties": {
  "AddressFamily": "ipv4",
- "IpamScopeId": "DefaultPrivateScope",
+ "IpamScopeId": {
+ "Fn::GetAtt": [
+ "IpamTestIpam6C9298EF",
+ "PrivateDefaultScopeId"
+ ]
+ },
  "Locale": "eu-central-1",
  "ProvisionedCidrs": [
  {
@@ -28,7 +33,12 @@
  "Properties": {
  "AddressFamily": "ipv6",
  "AwsService": "ec2",
- "IpamScopeId": "DefaultPublicScope",
+ "IpamScopeId": {
+ "Fn::GetAtt": [
+ "IpamTestIpam6C9298EF",
+ "PublicDefaultScopeId"
+ ]
+ },
  "Locale": "eu-central-1",
  "PublicIpSource": "amazon"
  }

packages/@aws-cdk/aws-ec2-alpha/test/integ.vpc-v2-alpha.ts

@@ -92,7 +92,7 @@ new SubnetV2(stack, 'testsubnet', {
  subnetType: SubnetType.PRIVATE_ISOLATED,
 });
 
-//validate ipv6
+//Validate ipv6 IPAM
 new SubnetV2(stack, 'validateIpv6', {
  vpc,
  ipv4CidrBlock: new IpCidr('10.3.0.0/24'),