selectors: Fix typo in comment.

Lib/selectors.py

@@ -419,7 +419,7 @@ if hasattr(select, 'epoll'):
                 # from zero to wait *at least* timeout seconds.
                 timeout = math.ceil(timeout * 1e3) * 1e-3
 
-            # epoll_wait() expectcs `maxevents` to be greater than zero;
+            # epoll_wait() expects `maxevents` to be greater than zero;
             # we want to make sure that `select()` can be called when no
             # FD is registered.
             max_ev = max(len(self._fd_to_key), 1)