java: Add spring-boot-starter-opendal

[Xuanwo]

Spring is a crucial framework in the Java ecosystem. It would be beneficial for OpenDAL to develop a spring-boot-starter-opendal, enabling Java users to seamlessly integrate OpenDAL immediately.

Notes

• We can place spring-boot-starter-opendal under integrations/spring-boot.

[shoothzj]

I can deep in that next week.

[Xuanwo]

I can deep in that next week.

Thanks a lot!