logs: log git fs mode

lib/platform/git/storage.js

@@ -29,6 +29,7 @@ class Storage {
 
     async function initRepo(args) {
       cleanRepo();
+      logger.info('Git FS mode enabled');
       config = { ...args };
       repoDir = await tmp.dir({ unsafeCleanup: true });
       git = Git(repoDir.path).silent(true);