Disable BatchTestContextCustomizer after AOT processing

[Hayvon]

nativeTest not using generated testAot sources

I have created a small reproducer application with Spring Batch. It contains a simple test which is working in jvm-mode and aot mode (-Dspring.aot.enabled=true) but not when I execute nativeTest.

It fails with following message:

org.springframework.boot.test.context.SpringBootTestAnnotation@d73e98da], contextLoader = org.springframework.boot.test.context.SpringBootContextLoader, parent = null]]
       org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:142)
       org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:127)
       org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependenciesInAotMode(DependencyInjectionTestExecutionListener.java:148)
       org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:94)
       org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:241)
       [...]
     Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'batchTestContextBeanPostProcessor': Runtime reflection is not supported for public org.springframework.batch.test.context.BatchTestContextBeanPostProcessor()
       org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1306)
       org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1198)
       org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:561)
       org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:521)
       org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:326)
       [...]
     Caused by: com.oracle.svm.core.jdk.UnsupportedFeatureError: Runtime reflection is not supported for public org.springframework.batch.test.context.BatchTestContextBeanPostProcessor()
       org.graalvm.nativeimage.builder/com.oracle.svm.core.util.VMError.unsupportedFeature(VMError.java:89)
       java.base@17.0.5/java.lang.reflect.Constructor.acquireConstructorAccessor(Constructor.java:68)
       java.base@17.0.5/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:496)
       java.base@17.0.5/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
       org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:197)
       [...]

This PR fixes the issue by disabling the BatchTestContextCustomizer after AOT processing

Used versions for reproducer:
Spring Boot 3.0.1
GraalVM Native Buildtools: 0.9.19
Java 17

[hpoettker]

Will this PR be included in the upcoming 5.0.1?

That would be great! Spring Framework is working on a nicer mechanism scoped for Spring 6.1 (spring-projects/spring-framework#29484). Until then, this seems to be the right approach as it is also used in the ContextCustomizer implementations in Spring Boot.

[fmbenhassine]

@hpoettker yes, I planned the fix for the upcoming 5.0.1

@Hayvon Thank you for raising the issue and fixing it! LGTM, rebased and merged as ed4a318. Thank you for your contribution!