Add tests to verify visibility of widget elements

[grzesiek2010]

Problem description

We have many widgets that represent different question types. The visibility of their elements depends on the state and might differ if:

• there is an answer vs there is no answer
• it's a read-only widget vs an editable widget etc.

we have some tests that verify that but not for every single widget and not for every single case. We need to review all widgets one by one and make sure there are tests confirming that the elements that the widget consists of are correctly displayed/hidden based on different states.

Other information

See the discussion https://github.com/getodk/collect/pull/5725#discussion_r1360619863