Closes gh-20467

Closes gh-20466

Closes gh-20465

Closes gh-20464

Closes gh-20463

Closes gh-20462

Closes gh-20461

Closes gh-20460

Closes gh-20459

Closes gh-20458

Closes gh-20457

Closes gh-20456

Closes gh-20455

Closes gh-20454

Closes gh-20453

Closes gh-20452

Closes gh-20451

Closes gh-20450

Closes gh-20449

Closes gh-20448

Closes gh-20447

Closes gh-20446

Closes gh-20445

Closes gh-20444

Closes gh-20443

Closes gh-20442

Changes in Gradle 6.2 should address the problems described in
4f75ab5f.

Closes gh-19609

See gh-4657

Standalone Jetty will, by default, include a Connection: close header
in all responses once graceful shutdown has begun. Previously, the
way in which we were shutting Jetty down did not cause this to happen.

This commit updates JettyGracefulShutdown to shut down each connector.
This causes Jetty to send the Connection: close header, aligning its
behaviour more closely with what it does when used standalone. The
tests have also been updated to verify this behaviour and to ensure
that the correct port is used for requests even once the connector is
no longer bound and the web server no longer knows its ephemeral port.

See gh-4657

See gh-4657

Closes gh-20433

Closes gh-20432

This reverts commit 6828a15d.
The commit has been reverted as it breaks backwards compatiblity.

Fixes gh-20343

See gh-4657

See gh-4657

This commit adds support for gracefully shutting down the embedded
web server. When a grace period is configured
(server.shutdown.grace-period), upon shutdown, the web server will no
longer permit new requests and will wait for up to the grace period
for active requests to complete.

Closes gh-4657

* pr/20428:
  Remove hardcoded version from VersionOverridingElasticsearchContainer

Closes gh-20428

See gh-20428

* pr/20419:
  Polish

Closes gh-20419