chore(ec2): pricing api interface vpc endpoint duplicated (#31912)

### Issue # (if applicable)

Closes #31911.

### Reason for this change
`InterfaceVpcEndpointAwsService('pricing.api')` enum duplicated.

https://github.com/aws/aws-cdk/blob/main/packages/aws-cdk-lib/aws-ec2/lib/vpc-endpoint.ts#L518
https://github.com/aws/aws-cdk/blob/main/packages/aws-cdk-lib/aws-ec2/lib/vpc-endpoint.ts#L520



One side should be deleted.

### Description of changes

Delete the enum that was added later.



### Description of how you validated changes
nothing because only enum changed



### 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: mazyu36

packages/aws-cdk-lib/aws-ec2/lib/vpc-endpoint.ts

@@ -517,7 +517,6 @@ export class InterfaceVpcEndpointAwsService implements IInterfaceVpcEndpointServ
   public static readonly PIPES_FIPS = new InterfaceVpcEndpointAwsService('pipes-fips');
   public static readonly PRICE_LIST = new InterfaceVpcEndpointAwsService('pricing.api');
   public static readonly POLLY = new InterfaceVpcEndpointAwsService('polly');
-  public static readonly PRICING_API = new InterfaceVpcEndpointAwsService('pricing.api');
   public static readonly PRIVATE_5G = new InterfaceVpcEndpointAwsService('private-networks');
   public static readonly PRIVATE_CERTIFICATE_AUTHORITY = new InterfaceVpcEndpointAwsService('acm-pca');
   public static readonly PRIVATE_CERTIFICATE_AUTHORITY_CONNECTOR_AD = new InterfaceVpcEndpointAwsService('pca-connector-ad');