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/ )

首先跟踪 AwsCrypto.decryptData/encryptData 和 KmsMasterKeyProvider，以了解每个请求的 AWS SDK v2 overrideConfiguration 可以在哪里引入。将现有的 API_NAMESPACE 用法与提出的两个选项进行比较，然后定义 encrypt 和 decrypt 所需的请求上下文及 API 形式。完成的标准是，一个 KmsClient 可以为多个账户的请求提供服务，并且额外的 header 可以传递到 KMS 调用中。

由索引模型根据 Issue 内容生成。