Merge pull request #17953 from nextcloud/backport/17942/stable16

[stable16] pass through ServerNotAvailableException on app init

Author: rullzer

lib/private/legacy/app.php

@@ -55,6 +55,7 @@
 use OC\DB\MigrationService;
 use OC\Installer;
 use OC\Repair;
+use OC\ServerNotAvailableException;
 use OCP\App\ManagerEvent;
 use OCP\ILogger;
 
@@ -153,6 +154,9 @@ public static function loadApp(string $app) {
 			try {
 				self::requireAppFile($app);
 			} catch (Throwable $ex) {
+				if($ex instanceof ServerNotAvailableException) {
+					throw $ex;
+				}
 				\OC::$server->getLogger()->logException($ex);
 				if (!\OC::$server->getAppManager()->isShipped($app)) {
 					// Only disable apps which are not shipped