The caching behaviour when using ImportAutoConfiguration is covered
by tests in spring-boot-test-auto-configuration, specifically by
ImportsContextCustomizerFactoryWithAutoConfigurationTests.

See gh-7953

* pull7948:
  Document AWS Elastic Beanstalk deployment

Update the reference documentation to include details of Amazon
Elastic Beanstalk.

Closes gh-7948

Update `ImportsContextCustomizer` so that whenever possible a more
specific cache key is used.

Prior to this commit the customizer would generate a key based on *all*
annotations on the test class. This has repeatedly caused issues where
test classes that should have the same cache key did not due to
unrelated annotations.

A new `DeterminableImports` interface has been added that can be
implemented by `ImportSelector` and `ImportBeanDefinitionRegistrar`
implementations that are able to determine their imports early. The
existing `ImportAutoConfigurationImportSelector` and
`AutoConfigurationPackages` classes have been retrofitted with
this interface.

Fixes gh-7953

Update `TypeExcludeFiltersContextCustomer` to use filter instances
as part of the key, rather than class references. In order to be used
in tests, `TypeExcludeFilter` implementations must now implement valid
`hashCode` and `equals` methods.

Fixes gh-8125

Previously, ManagementContextConfiguration classes were loaded to
allow them to be ordered based on either @Order or implementing
Ordered. This had the unwanted side-effect of possibly logging
unwanted INFO messages if the reflection-based annotation
introspection failed. One cause of this was @ConditionalOnClass when
the referenced class was not on the classpath.

This commit uses the ASM-based annotation metadata reading to
determine the order of a management context configuration class based
on the @Order annotation. The classes are then sorted using a standard
OrderComparator. Note that Ordering via implemented Ordered is not
supported as it cannot be determine without loading the class.

See gh-7579

Closes gh-8113

Closes gh-8112

Previously, Hibernate Validator would fail to initialize if it was
on the classpath but an EL implementation was not.
OnValidatorAvailableCondition protected against this scenario by
initializing the validator.

The Hibernate Validator shortcoming was addressed in eb222209
(gh-7598). As a result, checking for the precences of the
ValidationProvider META-INF/services resource is now sufficient to
auto-configure validation. This commit removes
OnValidatorAvailableCondition as it is no longer necessary.

Closes gh-8110

Closes gh-8114

Closes gh-7579

See gh-8112

Closes gh-8032

Update the open_source_licenses file to reflect the fact that the
org.json library is no longer used.

See gh-5929

Closes gh-7703

Update all `EmbeddedServletContainer` implementations to ensure that
the `start()` method can be called multiple times, with the second call
being ignored.

Fixes gh-8036

Update `Log4J2LoggingSystem` and `LogbackLoggingSystem` to ensure
that filters are removed when the `cleanUp` method is called. Prior
to this commit application failures would not remove the filter and
no log messages would appear.

The `LoggingApplicationListener` has also been updated since it
previously failed to handle `ApplicationFailureEvents`.

Finally `EventPublishingRunListener` and `DelegatingApplicationListener`
have been updated to deal with `null` parameters and to cope with
listener errors.

Fixes gh-7758

Closes gh-8008

This reverts commit 70cd5c42.

See gh-8083

In version 2.3.6 and earlier, an attempt to create a Bucket or a
ClusterInfo would fail fast with a ConnectException in the cause of
the Couchbase server was done. In 2.3.7 this remains true for a
Bucket but is no longer the case for ClusterInfo. The latter now
retries for 75 seconds by default and when it eventually fails a
ConnectException is no longer part of the cause chain.

This commit makes the auto-configured ClusterInfo depend on the
auto-configured Bucket. This means that the Bucket is always created
before the ClusterInfo, thereby ensuring that things fail gracefully
with useful diagnostics when the server is unavailable.

Closes gh-8092

Closes gh-7774

Previously, AbstractEmbeddedServletContainerFactory detected an
exploded war by looking for `/WEB-INF/` in the path of its code
source's location. This failed on Windows due to the use of `\` rather
than `/` separators.

This commit updates AbstractEmbeddedServletContainerFactory to
uses the OS's separator rather than hardcoding `/`.

Closes gh-8100