Cancelled and queued registrations in admin screen

[Scarletto]

Closes #179.

Summary

Added queued filter to API AdminEventRegistration request. Added lists of AdminEventRegistrations queuedRegistrations and cancelledRegistrations to EventAdminState and EventAdminCubit. Turned the EventAdminScreen into a screen with tabs, and gave queued and cancelled registrations their own type of tiles with useful info.

How to test

Steps to test the changes you made:

1. Go to any event.
2. Click on the gear icon to go to admin view.

Note about search

Search in its current form still only searches regular registrations. I think this is OK as this is the most relevant use of search, and I want to avoid double work because of #427.

[JAicewizard]

I rebased to make the it reviewable. I dont know if the registrations worked before. Cancelations also don't work. I canceled someone on the scarletto event (183) and they do not show up. This is a bug in concrexit so ill file an issue

[DeD1rk]

Not sure what's wrong on staging (have only tried on production) but this seems to work well on production (e.g. weekend has all types). One small thing: the tab headers should have just a single capital: they're not oswald. That will probably make it look much better and make the headers fit their 1/3rd width space

[JAicewizard]

See concrexit/#3315

[DeD1rk]

I fixed the things. Will try the testflight. @JAicewizard is it ready then?

[JAicewizard]

No don't merge yet, I want to relase a point release tomorrow (hopefully with the multiple backends). There are quite a few fixes in already. Then merge features, as there are quite a few almost empty.

[JAicewizard]

This looks good to merge BTW, rebased to maybe @Scarletto you can double check again?