remove `await asyncio.sleep(1)` after running a task.
remove `await asyncio.sleep(1)` after running a task.

We don't strictly need this sleep to make sure we're not blocking
background tasks, and it wastes valuable scriptworker execution time,
especially for workers with many short tasks, like beetmover.

escapewindow/scriptworker,escapewindow/scriptworker,mozilla-releng/scriptworker,mozilla-releng/scriptworker