Sporadic flowauth test fails

[greenape]

FlowAuth tests are periodically failing on the first test, e.g. https://circleci.com/gh/Flowminder/FlowKit/59539 or see https://dashboard.cypress.io/#/projects/67obxt/runs/2933/failures/9f4670b4-f665-4edb-afa0-5f4410600139

This seems to be because cypress is sometimes not sending the cookie.

[greenape]

Alternatively, and based on https://circleci.com/gh/Flowminder/FlowKit/59547

The reason this is sporadically failing is because there are actually multiple instances of the app being run by uwsgi, and hence the before_first_request functions can get called multiple times. This is most obviously an issue with the demo data creation, because that will drop all the existing data and recreate it.

[greenape]

I increasingly think that this is the issue actually - I reckon what's happening is that the demo data creation doesn't happen all in one transaction - the drop is one, the create is a second, and then the data gets populated in a third. So potentially, requests can get caught 'in between' these happening because of the multiple uwsgi workers.

[greenape]

The more I think about it, the more of a problem this is - for example, if the container is started with the RESET_FLOWAUTH_DB, you could end up unpredictably wiping the db :\