upgrade spring boot version to 4.0.3

[vzickner]

No description provided.

[filiphr]

I've left some comments inline. Let's keep the baseline to Java 17, there is no need to bump that.

We should also add the spring-boot-json dependency to the starter. Otherwise, the Jackson Auto Configuration does not kick in.

Can you also adjust the import order so that they follow the same pattern as https://github.com/flowable/flowable-engine/tree/main/ide-settings/idea

[filiphr]

@vzickner we are still missing:

We should also add the spring-boot-json dependency to the starter. Otherwise, the Jackson Auto Configuration does not kick in.

[filiphr]

Thanks @vzickner