Merge pull request #1425 from nextcloud/backport/1383/stable0.8

[stable0.8] fix(Import): expect selectionOptions as array from json

lib/Controller/ApiTablesController.php

@@ -158,7 +158,7 @@ public function createFromScheme(string $title, string $emoji, string $descripti
 						numberDecimals: $column['numberDecimals'],
 						numberPrefix: $column['numberPrefix'],
 						numberSuffix: $column['numberSuffix'],
-						selectionOptions: $column['selectionOptions'] == [] ? '' : $column['selectionOptions'],
+						selectionOptions: $column['selectionOptions'] === [] ? '' : \json_encode($column['selectionOptions'], JSON_THROW_ON_ERROR),
 						selectionDefault: $column['selectionDefault'],
 						datetimeDefault: $column['datetimeDefault'],
 						usergroupDefault: $column['usergroupDefault'][0] ?? '',