Fix ical import allowing caldav==1.4.0

[Oshgnacknak]

Arch Linux bumped the python-caldav package to version 1.4.0. This change broke errands on this distribution. Instead of a normal caldav sync taking place, the following error message was displayed:

Exception in thread Thread-1 (sync):
Traceback (most recent call last):
  File "/usr/lib/python3.12/threading.py", line 1075, in _bootstrap_inner
    self.run()
  File "/usr/lib/python3.12/threading.py", line 1012, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/share/errands/errands/lib/sync/sync.py", line 53, in sync
    self.provider.sync()
  File "/usr/share/errands/errands/lib/sync/providers/caldav.py", line 215, in sync
    self.__sync_lists()
  File "/usr/share/errands/errands/lib/sync/providers/caldav.py", line 235, in __sync_lists
    self.__update_local_list(cal, list)
  File "/usr/share/errands/errands/lib/sync/providers/caldav.py", line 298, in __update_local_list
    color = cal.get_property(caldav.elements.ical.CalendarColor())
                             ^^^^^^^^^^^^^^^^^^^^
AttributeError: module 'caldav.elements' has no attribute 'ical'

A simple import fix seems to do the trick. I have not tested if this fix also supports caldav==1.3.9, but I can imagine that it does.

Off Topic: I use Errands daily because it seems to be the only caldav client supported on Linux that allows nested todos to be synchronized via caldav. I would like to thank the developers for their time. My live unironically depends on errands to some decree.

• Osh

[mrvladus]

Thank you! I'm currently rewriting whole app in C, and I want to improve syncing as much as possible.