Easter isn't listed as a holiday for DE-HE 2021

[pmlk]

This issue came up after upgrading from 3.8.0 to 3.16.7. It seems to have started with version 3.15.0 3.14.5.

This may be related to #14, since Easter is always on a Sunday, it may not be considered a holiday. However, "2. Weichnachtstag" was also on a Sunday in 2021, but it is listed as a holiday. So if excluding all Sundays were a rule, it seems to be a bit inconsistent.

[commenthol]

Hi @pmlk, I have check the data in DE.yaml but there has not been an attribution on easter for Hessen so far.
If easter shall be added for DE-HE, please consider filing a PR.

[pmlk]

I'd be happy to file a PR, but I would need some help as I don't quite understand the syntax in the yaml files.

Also, I do see something for easter for DE-HE: https://github.com/commenthol/date-holidays/blob/master/data/countries/DE.yaml#L200

As said, it did show up before version 3.14.5, but I don't quite understand why it vanished.

[commenthol]

Hi @pmlk ,
I created PR#365 which should fix the issue. I would also consider Pentecost as public holiday then.
Please advise if changes are required.

[pmlk]

Awesome! Thank you! According to Wikipedia Pentecost is also a public holiday in Hessen. So that looks good to me 👍

Thank you so much! 🙏