Allow to pass overrideConfiguration per request

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### Problem:

If i want to pass additional headers with Decrypt call (e.g Confused Deputy protection). I need to provide for each account own KmsClient. Instead in SdkV2 i can call .overrideConfiguration on request (you already use it for API_NAMESPACE).

If it will be possible to add .overrideConfiguration per call encrypt/decrypt i can use the same KmsClient for all accounts.

### Solution:

A description of the possible solution in terms of Encryption SDK architecture.

I see 2 options:
1. in AwsCrypto.decryptData/ecryptData provide additional argument with options
2. When construct KmsMasterKeyProvider ask for supplier for override. But there we need to send something in addition to identify context of request

### Out of scope:

Is there anything the solution will intentionally NOT address?

[//]: # (NOTE: If you believe this might be a security issue, please email aws-security@amazon.com instead of creating a GitHub issue. For more details, see the AWS Vulnerability Reporting Guide: https://aws.amazon.com/security/vulnerability-reporting/ )

Commencez par suivre AwsCrypto.decryptData/encryptData et KmsMasterKeyProvider afin de comprendre où overrideConfiguration par requête de AWS SDK v2 pourrait être introduit. Comparez l’utilisation existante de API_NAMESPACE avec les deux options proposées, puis définissez le contexte de requête et la forme d’API nécessaires pour encrypt et decrypt. C’est terminé lorsqu’un KmsClient peut servir des requêtes pour plusieurs comptes et que des en-têtes supplémentaires parviennent à l’appel KMS.

Rédigé par le modèle d'indexation à partir du texte de l'issue.