Adds EoD Priority Strike to the /daily command

[ryanbillings]

This adds the EoD Priority Strike to the /daily command. It follows the same pattern as IBS daily strikes, and adds the list of strikes to the JSON data and then uses an index based on today's date.

We could probably update this to use the GW2 API, as there is now an achievement category endpoint that returns the IDs of the current strikes. Doing so would be future-proof to other strike additions. I didn't have the time at the moment, but I may do another PR in the future to make that update 😄

[Maselkov]

Thank you for the PR!

Yes, I agree, it'd be a good idea to futureproof using the APi. I might work on that at some point, but you'd be more than welcome to make a PR!

I think one could add it to the cache_dailies function, just need to add a strikes category, and make sure to account for filling out "tomorrow" too. https://github.com/Maselkov/GW2Bot/blob/9998f3d84147670ab54d56a8d35643ed103645b9/guildwars2/database.py#L183