Issue #3380571 by heddn: Convert protected members of final classes to private

automatic_updates_extensions/src/BatchProcessor.php

automatic_updates_extensions/src/Form/UpdaterForm.php

...dates_extensions/src/Validator/UpdateReleaseValidator.php

package_manager/src/Event/CollectPathsToExcludeEvent.php

package_manager/src/Event/PreApplyEvent.php

package_manager/src/Event/PreCreateEvent.php

package_manager/src/ProcessFactory.php

package_manager/src/Validator/DuplicateInfoFileValidator.php

...age_manager/src/Validator/EnvironmentSupportValidator.php

package_manager/src/Validator/LockFileValidator.php

package_manager/src/Validator/MultisiteValidator.php

package_manager/src/Validator/StageNotInActiveValidator.php

package_manager/src/Validator/SupportedReleaseValidator.php

...ckage_manager_bypass/src/ComposerStagerExceptionTrait.php

...ules/package_manager_bypass/src/LoggingDecoratorTrait.php

scripts/PackageManagerFixtureCreator.php

src/BatchProcessor.php

src/Form/UpdateReady.php

src/Form/UpdaterForm.php

src/ReleaseChooser.php