Remove the `spring-boot-web-server-test` module, adding
`SpringBootTestRandomPortContextCustomizerFactory` to
`spring-boot-web-server` as a replacement for
`SpringBootTestRandomPortApplicationListener`.
See gh-46356
See gh-47322
Relocate `RestTestClientBuilderCustomizer` to `spring-boot-test`
and break the direct link to web-server by making use of
`spring.factories` and the new `BaseUrlProviders` class.
See gh-46356
Make `spring-boot-test-autoconfigure` optionally depend on
`spring-boot-autoconfigure` so that it can be an `api` dependency
for `*-test` modules. Also relocate it to core.
See gh-47322
This commit modularizes spring-boot-test-autoconfigure. It now
contains only the code that's central to test auto-configuration.
Feature-specific functionality has moved out into -test modules,
some existing and some newly created. For example, `@DataJpaTest` can
now be found in spring-boot-data-jpa-test.
Closes gh-47322
Andy Wilkinson
Phillip Webb