Closes gh-14430

Closes gh-14431

Closes gh-14432

Closes gh-14433

Closes gh-14434

Closes gh-14435

Closes gh-14436

Closes gh-14437

Closes gh-14439

Closes gh-14441

Add log4j to `spring-boot-actuator-autoconfigure` test scope so that
we get valid log output.

See gh-14148

Replace Aether dependencies with Maven Resolver following the Eclipse
EOL announcement for Aether.

Closes gh-7627

Closes gh-14411

Closes gh-14422

Fixes gh-14148

Update `DevToolsPropertyDefaultsPostProcessor` to remove custom logging
level configuration. Unfortunately it's not easy to back-off logging
overrides when the user has a custom logback/log4j configuration.

Closes gh-14310

Update `SpringApplication` to automatically register the shared
`ApplicationConversionService` instance with the `BeanFactory` and
`Environment`.

Closes gh-12148

Also, @WebFluxTest now adds any ServerHttpSecurity beans
to the context.

Closes gh-13632

Relocate the 'spring.insights.web.log-request-details' property to
'spring.http.log-request-details'.

Closes gh-14313

Closes gh-14417

Closes gh-14158

Closes gh-14416

Closes gh-14415

Closes gh-14414

Closes gh-14409

Closes gh-14408

* gh-10275:
  Polish "Issue a warning from launch script when app will run as root"
  Issue a warning from launch script when app will run as root