Remove spring-boot-json-test module and spread code between
`spring-boot-test`, `spring-boot-test-autoconfigure` and JSON
technology modules.
See gh-46356
See gh-47322
We need to use Java 25 when using buildpacks to create a native image
for a couple of reasons:
- Framework has raised its GraalVM baseline to 25
- Buildpacks have removed support for Java 24
See gh-45501
Phillip Webb
Andy Wilkinson