As suggested by the support team the solution is
Service Principal Authentication following the same like below thread is not supported.:
https://github.com/MicrosoftDocs/azure-docs/issues/60204
Service Principal authentication with MySQL · Issue #60204 · MicrosoftDocs/azure-docs · GitHub
In terms of Service Principal the only type we support is Connect with Managed Identity - Azure Database for MySQL | Microsoft Learn
https://learn.microsoft.com/en-us/azure/mysql/howto-connect-with-managed-identity
the other alternative without managed identity is
add AAD group as MYSQL admin then use it to create other valid AAD group and account , SP can only be used for individual account in MYSQL and can't be used as admin to create other AAD group
follow link: https://learn.microsoft.com/en-us/azure/mysql/howto-configure-sign-in-azure-ad-authentication