TW configuration can now live in other places than `~/.taskrc` by default

[DDzwiedziu]

See https://github.com/GothenburgBitFactory/taskwarrior/blob/develop/src/Context.cpp#L496-L499 It was added ~11 years ago, as far as git-blame tells me, but the distro releases containing this change started rolling out recently.

So without manually setting $TASKRC you get this:

❯ task export | task2dot | dot -Tsvg > test.svg
Traceback (most recent call last):
  File "/home/dzwiedziu/.local/bin/task2dot", line 8, in <module>
    sys.exit(main())
  File "/home/dzwiedziu/.local/lib/python3.10/site-packages/task2dot/task2dot.py", line 539, in main
    edge_data = connector(task_data, get_udas_from_task_config())
  File "/home/dzwiedziu/.local/lib/python3.10/site-packages/task2dot/task2dot.py", line 330, in get_udas_from_task_config
    with open(config_file, 'r') as rc:
FileNotFoundError: [Errno 2] No such file or directory: '/home/dzwiedziu/.taskrc'