This is an alternative to the fix made in 3b52909f which removed the
chown call entirely.

Prior to 3b52909f, the ownership of $PID_FOLDER was always changed even
when its value was /var/run. This was problematic as it could prevent
other services from creating their pid folder or file.

When a sub-folder is used, changing its ownership so that it’s owned by
the user that will run the app is desirable as it limits access to the
folder. Rather than removing the chown call entirely, this commit
ensures that it only happens when a sub-folder is being used to hold the
pid file.

Closes gh-6532

Closes gh-6923

Closes gh-6922

Fixes gh-6521

* pr/6921:
  Polish

Update `@AutoConfigureMockMvc` with a `printOnlyOnFailure` option which
allows errors to be printed only when tests fail. Defaults to `true`
meaning the logs are no longer cluttered with MVC results for passing
tests.

Fixes gh-6653

Closes gh-6914 (I hope)

See gh-6918

Update WebDriver support to ensure that the `.quit()` method is called
after each test method runs and that a new WebDriver instance is
injected each time.

Support is provided by introducing a new `Scope` which is applied by
a ContextCustomizerFactory and reset by a TestExecutionListener.

Fixes gh-6641

Fixes gh-6916

* pr/6909:
  Link to Spring Security OAuth2 reference docs

Update documentation to include a link to Spring Security OAuth2's
reference documentation.

Closes gh-6909

* pr/6919:
  Add contextPath LocalHostUriTemplateHandler URIs

Update `LocalHostUriTemplateHandler` so that the `server.context-path`
property is also considered when building the URL.

Fixes gh-6904
Closes gh-6919

Fixes gh-6918

Refine @MockBean/@SpyBean qualifier support so that qualifiers form part
of the context cache key. Prior to this commit is was possible that two
different tests could accidentally share the same context if they
defined the same @Mock but with different @Qualifiers.

See gh-6753

See gh-6593

Tweak the fix from 50c68a49 to no longer print a link the reference
documentation.

See gh-6593

Update `@AutoConfigureTestDatabase` so that it always imports
`DataSourceAutoConfiguration`. Prior to this commit the annotation
could only be applied if something else also imported DataSource
auto-configuration.

Fixes gh-6897

Update the launch script so that it no longer changes ownership of the
PID_FOLDER.

Commit b24e736c had changed the chown
line from:
	chown "$run_user" "$PID_FOLDER/${identity}"
to:
	chown "$run_user" "$PID_FOLDER"

This meant that it was possible for the launch script to change
ownership of `/var/run` and prevent later processes from writing to
the folder.

Since PID_FOLDER is created before the chown statement, and that
the `checkPermissions` function runs to ensure that the PID file can
be written, it appears that the chown is not even required.

Fixes gh-6532

Add `spring.mvc.formcontent.putfilter.enabled` property to allow the
HttpPutFormContentFilter to be disabled.

Fixes gh-6519

Update `AbstractNestedCondition` to correctly group nested conditions
on members.

Fixes gh-6672

Closes gh-6835

See gh-6910

Add an explicit note that states that "spring.datasource.url" (or more
specifically "spring.datasource.class-name" that is inferred from the
former) is necessary to connect to a database. If the class-name isn't
specified, Spring Boot will attempt to auto-configure an embedded
database.

Closes gh-6907

This commit improves the startup error message so that it does not
reference  `--debug` anymore. Such command-line switch only works when
the application is started using `java -jar`.

The error message now refers directly to a section of the documentation
that provides more details and links to more useful examples.

Closes gh-6593

This commit fixes the documentation that wrongly states that
SpringBootWebSecurityConfiguration is an auto-configuration. Rather than
excluding this class, we should exclude SecurityAutoConfiguration that
imports it.

Closes gh-6861