Tasks about updating links in spring.io

[backwind1233]

Context We should update the link of https://spring.io/projects/spring-cloud-azure#samples when sample is adjusted. Now the link in https://spring.io/projects/spring-cloud-azure#samples is azure-spring-boot-samples.

Task

1. Rename folder name from aad to azure active directory now folder name aad is not consistant with offical doc, may be confusing.
   • [ ] rename folder @backwind1233
   • [x] Update spring reference yaml
   • [x] update links in samples, azure-sdk-for-java,azure-dev-docs-pr

• [x] Update sample links in spring.io