* gh-15885:
  Clean up SpringPropertyAction.getValue()

Closes gh-15885

See gh-15885

* gh-15854:
  Polish "Remove dependency management for xml-apis"
  Remove dependency management for xml-apis

Closes gh-15854

See gh-15854

See gh-15854

* gh-15889:
  Do not auto-configure OEMIV filter when user defines registration bean

Closes gh-15889

See gh-15889

* gh-15876:
  Polish "Remove unwanted @Nullable annotations"
  Remove unwanted @Nullable annotations

Closes gh-15876

See gh-15876

See gh-15876

Closes gh-15892

* gh-15791:
  Polish "Test the Gradle plugin against Gradle 4.10.3 and 5.1.1"
  Test the Gradle plugin against Gradle 4.10.3 and 5.1.1

Closes gh-15791

See gh-15791

* pr/15823:
  Polish

Closes gh-15823

* pr/15837:
  Polish

1. Removed unnecessary null checks
2. Combined collection initialization and modification
3. Minor collections related optimizations

Closes gh-15837

* pr/15883:
  Fix broken link to Appendix

Closes gh-15883

This commit also ensures that Jersey-based actuator endpoints are
available before the user has configured a `ResourceConfig` bean

Fixes gh-15625
Fixes gh-15877

See gh-15878

Previously, if profiles were included via a property source with higher
precedence than config files, profiles activated via config files would
not be taken into account. This commit makes spring.profiles.include
behave consistently where it adds to active profiles rather than replacing
them, regardless of property source.

Fixes gh-15344

Prior to this commit, the `HttpTraceWebFilter` would collect the
response information (status and headers) for tracing purposes, after
the handling chain is done with the exchange - inside a
`doAfterSuccessOrError`.

Once the handler has processed the exchange, there is no strong
guarantee about the HTTP resources being still present. Depending on the
web server implementation, HTTP resources (including HTTP header maps)
might be recycled, because pooled in the first place.

This commit moves the collection and processing of the HTTP trace right
before the response is committed. This removes the need to handle
special cases with exceptions, since by that time all exception handlers
have processed the response and the information that we extract is the
information that's about to be written to the network.

Fixes gh-15819

Prior to this commit, errors unhandled by custom `WebExceptionHandler`
and resulting in an HTTP 500 status would not be logged at ERROR level,
giving no information to developers about the actual exception.

This commit ensures that such exceptions are logged at the ERROR level
with their exception. By the time the exception hits the
`DefaultErrorWebExceptionHandler`, if the response is already committed
or if the exception is due to a client disconnecting, the error is
delegated to Framework support as Spring Boot won't be able to render an
error page as expected.

Fixes gh-15769

See gh-15873

* pr/15873:
  Polish

Closes gh-15873

* pr/15871:
  Fix assertion

Closes gh-15871