Execute command can no longer return null, must be an integer.

Author: Adambean

src/LdapSyncCommand.php

@@ -241,9 +241,9 @@ public function configure(): void
      * @param InputInterface  $input  Input interface
      * @param OutputInterface $output Output interface
      *
-     * @return int|null Error code, or null/zero for success
+     * @return int Error code, or null/zero for success
      */
-    public function execute(InputInterface $input, OutputInterface $output): ?int
+    public function execute(InputInterface $input, OutputInterface $output): int
     {
         $this->output = $output;
         $this->logger = new ConsoleLogger($output);