See gh-20806

See gh-20806

Closes gh-21119

* pr/21077:
  Polish "Enhance Database initialization how to guide"
  Enhance Database initialization how to guide

Closes gh-21077

See gh-21077

See gh-21077

Closes gh-21118

* pr/21002:
  Fix typo

Closes gh-21002

See gh-21002

* pr/21117:
  Remove unused method

Closes gh-21117

See gh-21117

* pr/21110:
  Polish

Closes gh-21110

See gh-21110

* pr/21103:
  Avoid recompiling pattern in Handler#canonicalize

Closes gh-21103

See gh-21103

* pr/21079:
  Fix link to R2DBC Query in docs

Closes gh-21079

See gh-21079

* pr/21054:
  Fix Actuator API PDF name

Closes gh-21054

See gh-21054

* pr/21009:
  Update copyright year of changed file
  Polish

Closes gh-21009

See gh-21009

See gh-21009

* pr/21007:
  Update copyright year of changed files
  Remove this keyword on member method invocations

Closes gh-21007

See gh-21007

See gh-21007

* pr/20992:
  Polish ApplicationHome

Closes gh-20992

See gh-20992

Closes gh-21112

Closes gh-21111

Starting the CouchbaseContainer fails intermittently when creation
of the primary index for the bucket fails with a read timeout. The
test doesn't require a primary index for the bucket so this commit
disables it creation in the hope that it will help to stabilise the
test.

Previously, DefaultResourceLoader instances were created using the
default constructor. This causes the resource loader to capture the
TCCL that was in place at that time. This can lead to a class loader
leak if the resource loader is referenced directly or indirectly from
a static field of a class loaded by a different class loader.

This commit updates the creation of DefaultResourceLoader instances
in main code so that the resource load will use the class loader of
the creating class. In almost all cases this will be the same class
loader as was the thread context class loader that was being captured
so the change in behavior is minimal. Crucially, it will still address
the situation where the TCCL was different.

Note the DevTools' ApplicationContextResourceLoader has been updated
to explicitly use the TCCL. This ensures that it uses the restart
class loader which is required for DevTools to function correctly.

Fixes gh-20900

Closes gh-20823

Close gh-20507 in 2.3.0.RC1

Closes gh-21106

Improve "@ConfigurationProperties vs. @Value" documentation with the
recommendation that kebab-case is used with the `@Value` annotation.

Closes gh-20507

* pr/21104:
  Fix PropertiesMigrationListenerTests

Closes gh-21104

See gh-21104