Fix scrutinizer issues

Author: tvdijen

src/XML/xenc/EncryptedData.php

@@ -10,7 +10,6 @@
 use SimpleSAML\XML\{SchemaValidatableElementInterface, SchemaValidatableElementTrait};
 use SimpleSAML\XML\Type\{AnyURIValue, IDValue, StringValue};
 use SimpleSAML\XMLSecurity\XML\ds\KeyInfo;
-use SimpleSAML\XMLSecurity\XML\xenc\{CipherData, EncryptionMethod};
 
 use function array_pop;
 

src/XML/xenc11/AbstractKeyDerivationMethodType.php

@@ -66,7 +66,7 @@ public static function fromXML(DOMElement $xml): static
         Assert::same($xml->namespaceURI, static::getNamespaceURI(), InvalidDOMElementException::class);
 
         return new static(
-            self::getOptionalAttribute($xml, 'Algorithm', AnyURIValue::class, null),
+            self::getAttribute($xml, 'Algorithm', AnyURIValue::class),
             self::getChildElementsFromXML($xml),
         );
     }

src/XML/xenc11/MGF.php

@@ -28,7 +28,7 @@ public static function fromXML(DOMElement $xml): static
         Assert::same($xml->namespaceURI, static::getNamespaceURI(), InvalidDOMElementException::class);
 
         return new static(
-            self::getOptionalAttribute($xml, 'Algorithm', AnyURIValue::class, null),
+            self::getAttribute($xml, 'Algorithm', AnyURIValue::class),
         );
     }
 }

src/XML/xenc11/OtherSource.php

@@ -33,7 +33,7 @@ public static function fromXML(DOMElement $xml): static
         Assert::maxCount($parameter, 1, TooManyElementsException::class);
 
         return new static(
-            self::getOptionalAttribute($xml, 'Algorithm', AnyURIValue::class, null),
+            self::getAttribute($xml, 'Algorithm', AnyURIValue::class),
             array_pop($parameter),
         );
     }

src/XML/xenc11/PRF.php

@@ -28,7 +28,7 @@ public static function fromXML(DOMElement $xml): static
         Assert::same($xml->namespaceURI, static::getNamespaceURI(), InvalidDOMElementException::class);
 
         return new static(
-            self::getOptionalAttribute($xml, 'Algorithm', AnyURIValue::class, null),
+            self::getAttribute($xml, 'Algorithm', AnyURIValue::class),
         );
     }
 }