There is no official document for spring vault to integrated with Azure Key Vault.
From this spring boot official document it only say about HashiCorp’s vault integration.There is no other cloud platform other than HashiCorp’s vault integrate with spring cloud vault.
Spring Cloud Vault Config provides client-side support for
externalized configuration in a distributed system. With HashiCorp’s
Vault you have a central place to manage external secret properties
for applications across all environments. Vault can manage static and
dynamic secrets such as username/password for remote
applications/resources and provide credentials for external services
such as MySQL, PostgreSQL, Apache Cassandra, MongoDB, Consul, AWS and
more.
But you can access the azure key vault using the access key in your spring boot application for that you can refer the same document
Reference : https://spring.io/projects/spring-vault#overview