Incorrect version for aws-cryptographic-material-providers in README

**Summary**

The README for the AWS Encryption SDK Java lists the following dependency:

```xml

software.amazon.cryptography
aws-cryptographic-material-providers
3.0.2

```

However, version **3.0.2 does not exist on Maven Central**.
The latest available version is 1.11.0 as can be seen in the image below

**Suggested fix**
Update the README to use a valid version:

```xml
1.11.0
```

打开 README，找到 issue 中显示的 aws-cryptographic-material-providers 依赖项。对照 Maven Central 验证列出的版本，将其更新为 1.11.0，并确认依赖项示例现在使用的是有效版本。

由索引模型根据 Issue 内容生成。