fix #1980 user defined property metadata takes precedence

Change priority of user-defined metadata services to 20

Author: abluchet

src/Bridge/Symfony/Bundle/Resources/config/metadata/annotation.xml

@@ -29,7 +29,7 @@
         </service>
         -->
 
-        <service id="api_platform.metadata.property.metadata_factory.annotation" decorates="api_platform.metadata.property.metadata_factory" decoration-priority="40" class="ApiPlatform\Core\Metadata\Property\Factory\AnnotationPropertyMetadataFactory" public="false">
+        <service id="api_platform.metadata.property.metadata_factory.annotation" decorates="api_platform.metadata.property.metadata_factory" decoration-priority="20" class="ApiPlatform\Core\Metadata\Property\Factory\AnnotationPropertyMetadataFactory" public="false">
             <argument type="service" id="annotation_reader" />
             <argument type="service" id="api_platform.metadata.property.metadata_factory.annotation.inner" />
         </service>

src/Bridge/Symfony/Bundle/Resources/config/metadata/xml.xml

@@ -23,7 +23,7 @@
         </service>
 
         <service id="api_platform.metadata.property.metadata_factory" alias="api_platform.metadata.property.metadata_factory.xml" />
-        <service id="api_platform.metadata.property.metadata_factory.xml" class="ApiPlatform\Core\Metadata\Property\Factory\ExtractorPropertyMetadataFactory" public="false">
+        <service id="api_platform.metadata.property.metadata_factory.xml" class="ApiPlatform\Core\Metadata\Property\Factory\ExtractorPropertyMetadataFactory" decoration-priority="20" public="false">
             <argument type="service" id="api_platform.metadata.extractor.xml" />
         </service>
     </services>

src/Bridge/Symfony/Bundle/Resources/config/metadata/yaml.xml

@@ -22,7 +22,7 @@
             <argument type="service" id="api_platform.metadata.property.name_collection_factory.yaml.inner" />
         </service>
 
-        <service id="api_platform.metadata.property.metadata_factory.yaml" class="ApiPlatform\Core\Metadata\Property\Factory\ExtractorPropertyMetadataFactory" decorates="api_platform.metadata.property.metadata_factory" decoration-priority="40" public="false">
+        <service id="api_platform.metadata.property.metadata_factory.yaml" class="ApiPlatform\Core\Metadata\Property\Factory\ExtractorPropertyMetadataFactory" decorates="api_platform.metadata.property.metadata_factory" decoration-priority="20" public="false">
             <argument type="service" id="api_platform.metadata.extractor.yaml" />
             <argument type="service" id="api_platform.metadata.property.metadata_factory.yaml.inner" />
         </service>