[export] add a grouping of accompanying period by opening and closing date

src/Bundle/ChillPersonBundle/Export/Enum/DateGroupingChoiceEnum.php

@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\PersonBundle\Export\Enum;
+
+enum DateGroupingChoiceEnum: string
+{
+    case MONTH = 'YYYY-MM';
+    case WEEK = 'YYYY-IW';
+    case YEAR = 'YYYY';
+}