Declare strict types in all new Event classes

Signed-off-by: Côme Chilliet <come.chilliet@nextcloud.com>

lib/private/DB/MigratorExecuteSqlEvent.php

 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022 Côme Chilliet <come.chilliet@nextcloud.com>
  *

lib/private/Repair/Events/RepairAdvanceEvent.php

 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022 Côme Chilliet <come.chilliet@nextcloud.com>
  *

lib/private/Repair/Events/RepairErrorEvent.php

 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022 Côme Chilliet <come.chilliet@nextcloud.com>
  *

lib/private/Repair/Events/RepairFinishEvent.php

 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022 Côme Chilliet <come.chilliet@nextcloud.com>
  *

lib/private/Repair/Events/RepairInfoEvent.php

 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022 Côme Chilliet <come.chilliet@nextcloud.com>
  *

lib/private/Repair/Events/RepairStartEvent.php

 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022 Côme Chilliet <come.chilliet@nextcloud.com>
  *

lib/private/Repair/Events/RepairStepEvent.php

 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022 Côme Chilliet <come.chilliet@nextcloud.com>
  *

lib/private/Repair/Events/RepairWarningEvent.php

 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022 Côme Chilliet <come.chilliet@nextcloud.com>
  *