Removed the assertion which doesn't work with a user-provided PDO connection

lib/Doctrine/DBAL/Connection.php

@@ -1429,7 +1429,6 @@ class Connection implements DriverConnection
     public function getWrappedConnection()
     {
         $this->connect();
-        assert($this->_conn instanceof DriverConnection);
 
         return $this->_conn;
     }

tests/Doctrine/Tests/DBAL/Functional/ConnectionTest.php

@@ -12,6 +12,7 @@ use Doctrine\DBAL\Types\Types;
 use Doctrine\Tests\DbalFunctionalTestCase;
 use Error;
 use Exception;
+use PDO;
 use RuntimeException;
 use Throwable;
 use function in_array;
@@ -311,4 +312,16 @@ class ConnectionTest extends DbalFunctionalTestCase
 
         $connection->close();
     }
+
+    /**
+     * @requires extension pdo_sqlite
+     */
+    public function testUserProvidedPDOConnection() : void
+    {
+        self::assertTrue(
+            DriverManager::getConnection([
+                'pdo' => new PDO('sqlite::memory:'),
+            ])->ping()
+        );
+    }
 }