Update Spring Cloud Azure README file

[saragluna]

Description

This PR will update the Spring Cloud Azure readme file to:

• Include the supported versions of Spring Cloud Azure
• Add section for Spring Boot 3.x
• Add description for users who runs into the signed jar issue when building native executable.

All SDK Contribution checklist:

• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.

General Guidelines and Best Practices

• Title of the pull request is clear and informative.
• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• Pull request includes test coverage for the included changes.