Refactor `ReactiveWebApplicationContext` implementations to align closer
with the `WebApplicationContext` implementations defined in
Spring Framework.
The following classes are now provided:
- `AnnotationConfigReactiveWebApplicationContext` -- A refreshable
reactive web context with support for `@Configuration` classes.
- `GenericReactiveWebApplicationContext` -- A non-refreshable reactive
GenericApplicationContext.
- `ReactiveWebServerApplicationContext` -- A non-refreshable reactive
GenericApplicationContext with support for server discovery.
- `AnnotationConfigReactiveWebServerApplicationContext` -- A
non-refreshable reactive `GenericApplicationContext` with support
for `@Configuration` classes and server discovery.
These classes roughly align to the following Servlet equivalents:
- `AnnotationConfigWebApplicationContext` (Spring Framework)
- `GenericWebApplicationContext` (Spring Framework)
- `ServletWebServerApplicationContext` (Spring Boot)
- `AnnotationConfigServletWebServerApplicationContext` (Spring Boot)
An additional `ConfigurableReactiveWebEnvironment` interface as also
been introduced, primarily for `@ConditionalOnWebApplication` to use.
Fixes gh-10852
fa191d8c73