Issue #3456335 by pdureau: EnumPropType: Labelled enumerations

modules/ui_patterns_legacy/src/PropConverter.php

src/Element/ComponentPropForm.php

src/Plugin/UiPatterns/PropType/EnumListPropType.php

src/Plugin/UiPatterns/PropType/EnumPropType.php

src/Plugin/UiPatterns/Source/CheckboxesWidget.php

src/Plugin/UiPatterns/Source/SelectWidget.php

src/PropTypePluginBase.php

src/SchemaManager/Canonicalizer.php

src/SchemaManager/CompatibilityChecker.php

...omponents/prop_types_tests/prop_types_tests.component.yml

...ns_test/components/prop_types_tests/prop_types_tests.twig