PIM-7684: Fix async handle() signature to match sync version

The consolidation in 932ed19 made `objects` a required parameter
in the async CloudDrive.handle() but optional in the sync version.
This broke callers that use handle(path) for single-file reads.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: udirctera

cterasdk/asynchronous/core/files/browser.py

@@ -11,7 +11,7 @@
 class FileBrowser(BaseCommand):
     """Async File Browser API."""
 
-    async def handle(self, path, objects):
+    async def handle(self, path, objects=None):
         """
         Get a file handle.