Upgrade Project to Spring Boot 3

[seljabali]

Feel free to create a new project from https://start.spring.io to replace this one.

[hantsy]

Currently Spring Boot 3 just started its first milestone, I think at the end of this year, maybe it will release a stable version(new native build, new Spring observablity module).

I have created a branch and PR for it, the current codes is working well with Spring Boot 3.0.0-M1, I only changed the version and add Maven URL for deps and Gradle plugins.

[hantsy]

see: #14