Younger phpunit come with a happy little feature
to suppress E_DEPRECATED and E_USER_DEPRECATED
errors: The attribute `#[IgnoreDeprecations]` makes
a test not fail when such a deprecation is triggered
by the test subject, even when failOnDeprecation=true
is set in phpunit XML.

Using the attribute has been recommended by phpunit
maintainer Sebastian Bergmann.

This allows us to give up on the current strategy of
moving tests that test deprecated subjects to an own
directory. This simplifies maintenance, makes
patches that deprecate things more easy to review,
and saves some CI jobs.

During 'deprecation removal phase' at the beginning
of new major branches, we now simply look up usages
of the attribute to see what needs to be removed.

The patch takes care of 'UnitDeprecated' tests by
merging them back into 'Unit' and adding the
attribute. It also adapts runTests.sh to remove
the `-s unitDeprecated` test suite and adapts CI.
'FunctionalDeprecated' will follow with a separate
patch.

Resolves: #104582
Releases: main
Change-Id: I44473b04b3fe800a6fdd4032c6b2bd7682810979
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/85572


Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Simon Praetorius <simon@praetorius.me>
Reviewed-by: Andreas Kienast <a.fernandez@scripting-base.de>
Tested-by: Simon Praetorius <simon@praetorius.me>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Andreas Kienast <a.fernandez@scripting-base.de>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>