[pre-commit.ci] auto fixes from pre-commit.com hooks

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khal/controllers.py

@@ -27,7 +27,7 @@
 import textwrap
 from collections import OrderedDict, defaultdict
 from shutil import get_terminal_size
-from typing import Callable, Iterable, List, Optional
+from typing import Callable, List, Optional
 
 import pytz
 from click import confirm, echo, prompt, style