Cleanup unit tests

Author: tvdijen

tests/src/SAML11/XML/saml/StatementTest.php

@@ -104,7 +104,6 @@ public function testMarshalling(): void
     public function testUnmarshalling(): void
     {
         $statement = CustomStatement::fromXML(self::$xmlRepresentation->documentElement);
-        $this->assertInstanceOf(CustomStatement::class, $statement);
 
         $this->assertEquals('ssp:CustomStatementType', $statement->getXsiType());
         $audience = $statement->getAudience();

tests/src/SAML11/XML/saml/SubjectStatementTest.php

@@ -189,7 +189,6 @@ public function testMarshalling(): void
     public function testUnmarshalling(): void
     {
         $subjectStatement = CustomSubjectStatement::fromXML(self::$xmlRepresentation->documentElement);
-        $this->assertInstanceOf(CustomSubjectStatement::class, $subjectStatement);
 
         $this->assertEquals('ssp:CustomSubjectStatementType', $subjectStatement->getXsiType());
         $audience = $subjectStatement->getAudience();