Reinstate test now that we are on a reactor-netty releases that fixes
reactor/reactor-netty issue 1093.

Closes gh-21437

Further attempt to fix Windows file issues.

See gh-21575

Update `BuildRequest` to also allow digest based references.

Closes gh-21879

Refactor the internals of `PropertiesLauncher` so that opened jar files
are tracked and can be closed after a test completes.

See gh-21575

Update Ant smoke test to explicitly use Java 8.

* pr/21872:
  Fix deprecation in NettyRSocketServerFactoryTests

Closes gh-21872

See gh-21872

* pr/21793:
  Link complete Slack message to build log

Closes gh-21793

See gh-21793

This commit changes the NamedPipeSocket used for communication with
a local Docker daemon to use a non-blocking AsynchronousByteChannel
instead of a blocking RandomAccessFile, modeled after a similar
change to the docker-java project. This eliminates the potential for
a blocking call to hang indefinitely.

Fixes gh-21672

Pick up the workaround for the AsciidoctorJ bug that prevents the
configprops macro's attributes from being parsed. The lack of parsing
meant that the envvar format was being lost and properties were being
written in the canonical form instead.

Closes gh-21794

Closes gh-21889

Closes gh-21487

Closes gh-21784

Closes gh-21783

Closes gh-21776

Closes gh-21779

Closes gh-21782

Closes gh-21888

Closes gh-21781

Closes gh-21887

Closes gh-21886

Closes gh-21780

See gh-21885

Closes gh-21880

This commit aligns log4j2's behavior with logback such that loggers
with a null configuredLevel are also returned by the actuator endpoint.

Fixes gh-20037

Fixes gh-21293