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/ )

Beginne damit, AwsCrypto.decryptData/encryptData und KmsMasterKeyProvider nachzuverfolgen, um zu verstehen, wo die per-request AWS SDK v2 overrideConfiguration einfließen könnte. Vergleiche die bestehende Verwendung von API_NAMESPACE mit den beiden vorgeschlagenen Optionen und definiere anschließend den erforderlichen Request-Kontext und die API-Struktur für encrypt und decrypt. Erledigt bedeutet, dass ein KmsClient Anfragen für mehrere Konten bedienen kann und zusätzliche Header den KMS-Aufruf erreichen.

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