[5.x] Replaced a too strict assertion in DatabaseSessionHandler.php that prevented to use the sessions at all with a more simple sanity check. Test already failed on that, now they pass.

phpunit.xml.dist

@@ -23,6 +23,7 @@
         <env name="QUEUE_CONNECTION" value="database"/>
         <ini name="xdebug.mode" value="coverage"/>
         <ini name="memory_limit" value="-1"/>
+        <ini name="zend.assertions" value="1"/>
     </php>
 
     <source restrictDeprecations="true"

src/Session/MongoDbSessionHandler.php

@@ -56,9 +56,9 @@
                 'typeMap' => ['root' => 'bson'],
             ],
         );
-        assert($result instanceof Document);
 
-        return $result ? (string) $result->payload : false;
+
+        return $result?->payload ? (string) $result->payload : false;
     }
 
     public function write($sessionId, $data): bool