community/py3-tempora: add py3-dateutil to depends

Fix ModuleNotFoundError when importing tempora, found during a rebuild of py3-yg.lockfile on a 3.21 builder. The tests were unable to import tempora due to missing the dateutil module. Confirmed the addition of dateutil fixes the tests.

ImportError while importing test module '/home/buildozer/aports/community/py3-yg.lockfile/src/yg.lockfile-2.3/yg/lockfile/__init__.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
/usr/lib/python3.12/importlib/__init__.py:90: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
yg/lockfile/__init__.py:15: in <module>
    from tempora import timing
/usr/lib/python3.12/site-packages/tempora/__init__.py:13: in <module>
    import dateutil.parser
E   ModuleNotFoundError: No module named 'dateutil'