Issue #2351847 by damiankloip: Fixed Rename getCacheTag() to getCacheTags().

core/lib/Drupal/Core/Access/AccessResult.php

core/lib/Drupal/Core/Config/Entity/ConfigEntityBase.php

core/lib/Drupal/Core/Datetime/Entity/DateFormat.php

core/lib/Drupal/Core/Entity/Entity.php

core/lib/Drupal/Core/Entity/EntityInterface.php

core/lib/Drupal/Core/Entity/EntityViewBuilder.php

core/lib/Drupal/Core/Entity/EntityViewBuilderInterface.php

core/modules/aggregator/src/Entity/Item.php

...dules/aggregator/src/Plugin/Block/AggregatorFeedBlock.php

core/modules/aggregator/src/Tests/ItemCacheTagsTest.php

core/modules/block/src/BlockViewBuilder.php

core/modules/block/src/Entity/Block.php

core/modules/ckeditor/src/Plugin/CKEditorPlugin/Internal.php

...c/Unit/Access/ContentTranslationManageAccessCheckTest.php

.../modules/editor/src/Plugin/Filter/EditorFileReference.php

...lugin/Field/FieldFormatter/EntityReferenceIdFormatter.php

...in/Field/FieldFormatter/EntityReferenceLabelFormatter.php

...tity_reference/src/Tests/EntityReferenceFormatterTest.php

core/modules/filter/src/Element/ProcessedText.php

core/modules/filter/src/FilterProcessResult.php