Initial e2e-tests

[magdapoppins]

Fixes #17

Purpose

In addition to our unit test, let's have a set of e2e-tests that ensure that the page works and looks as expected. I chose cypress for this purpose since the NextJS docs point at it as an easy starting point.

How to test

Run yarn cypress and the example test.

[codecov]

Codecov Report

Merging #26 (22e995d) into main (ba4995c) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main      #26   +/-   ##
=======================================
  Coverage   99.07%   99.07%           
=======================================
  Files           8        8           
  Lines         108      108           
  Branches       22       22           
=======================================
  Hits          107      107           
  Partials        1        1           

Flag	Coverage Δ
db-unittests	100.00% <ø> (ø)
ui-unittests	98.07% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
components/pages/Homepage/EventCard.tsx	95.45% <ø> (ø)

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[lauravuo]

Is it cypress style to have the tests in folder cypress ? I mean, does the gh action require it? I would use e2e.

[eevajonnapanula]

Overall looking good 👍🏻 One think I think should be changed is the way to reach the tested element; so, use (for example) data-cy instead of redundant class name :) See the comments for exact places. More information about data-cy etc.

[magdapoppins]

@lauravuo I think the cypress folder is a cypress convention. We could apparently change it to e.g. "e2e" but that seems to require a a few different configs being changed (they don't seem to have a single option to change the test folder name). Should we still change it or is the current way ok?

As it is now yarn cypress creates a new "cypress" folder each time it's run if there isn't one already. :D

[lauravuo]

@magdapoppins if it is convention, then it is ok!

Fixed comments + taking Lauras approval!