Merge pull request #7 from muffix/add-notification

Add support for notificaitons through ntfy.sh

Merge pull request #6 from muffix/support-variants

The BayIMCO API has changed and now requires the vaccination number
(first, second or boost) to find available appointments. In the case of
a second jab, it also requires the variant used for the first one.

This change updates the checker to support that.

Additionally, filtering for vaccines targeting a specific variant is now
supported.

Add pre-commit hooks

Support `--latest-day`

Allows users to specify the latest acceptable date for an appointment.
By using `--earliest-day` and `--latest-day`, we can now specify an
exact time range for the appointment.

Fix earliest_day parameter

Fixes a bug where we're trying to work with an earliest day that might
be None.

Fixes: #1

Publish to Github Packages when creating a release

Publishes a Docker image to Github Packages when creating a release