chore(ec2): fix an incorrect import of ValidationError (#33897)

### Reason for this change

I'd missed an incorrect import of `ValidationError` in #33619

### 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)

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

Author: Tietew

packages/aws-cdk-lib/aws-ec2/lib/prefix-list.ts

@@ -1,8 +1,7 @@
 import { Construct } from 'constructs';
-import { ValidationError } from 'jsonschema';
 import { CfnPrefixList } from './ec2.generated';
 import * as cxschema from '../../cloud-assembly-schema';
-import { IResource, Lazy, Resource, Names, ContextProvider, Token } from '../../core';
+import { IResource, Lazy, Resource, Names, ContextProvider, Token, ValidationError } from '../../core';
 import { addConstructMetadata } from '../../core/lib/metadata-resource';
 
 /**