Locales updated

We have fixed some errors in the DE and US locales.

We fixed the region code for Bremen in the DE locale (see #103). Now, it is correctly listed as HB as specified in ISO 3166-2:DE.
Thanks to Olaf Sebelin for spotting that error.

We also fixed the calculation of the Day after Thanksgiving in the US locales (see #102). The 4th Friday is not always after the 4th Thursday in a month… šŸ˜…
Thanks to Peter J. Mello for reporting.

Those fixes not only affected 2024, but also some past holiday files which have been updated accordingly.