Fix expire date capability for federated shares

Signed-off-by: Vincent Petry <vincent@nextcloud.com>

apps/files_sharing/lib/Capabilities.php

@@ -111,7 +111,10 @@ class Capabilities implements ICapability {
 		$res['federation'] = [
 			'outgoing' => $this->config->getAppValue('files_sharing', 'outgoing_server2server_share_enabled', 'yes') === 'yes',
 			'incoming' => $this->config->getAppValue('files_sharing', 'incoming_server2server_share_enabled', 'yes') === 'yes',
-			'expire_date' => ['enabled' => true]
+			// old bogus one, expire_date was not working before, keeping for compatibility
+			'expire_date' => ['enabled' => true],
+			// the real deal, signifies that expiration date can be set on federated shares
+			'expire_date_supported' => ['enabled' => true],
 		];
 
 		// Sharee searches