datetime.utcnow() deprecation

[edsu]

I noticed some warnings popping up during testing a library under python v3.12 that depends on sqlite_migrate and figured I'd send along the small change.

tests/test_sqlite_migrate.py: 4 warnings
tests/test_sqlite_utils_migrate_command.py: 9 warnings
  /Users/edsummers/.local/share/virtualenvs/sqlite-migrate-kmlAZzTv/lib/python3.12/site-packages/sqlite_migrate/__init__.py:80: DeprecationWarning: datetime.datetime.utcnow() is deprecated and scheduled for removal in a future version. Use timezone-aware objects to represent datetimes in UTC: datetime.datetime.now(datetime.UTC).
    "applied_at": str(datetime.datetime.utcnow()),

Thanks for a useful module, and for the sqlite-utils/datasette ecosystem!

[simonw]

Thanks for this!

[simonw]

Tests fail in 3.8 and 3.9 because datetime.UTC is a more recent thing.

I'll try datetime.timezone.utc.