Paper should not validate without venue

[swt2public]

Scenario

When creating a paper without venue Then validation should fail

Hints

Papers should not be valid without having all attributes (title, venue and year) set. Year should be a numeric value.

Validation reference

Error

Expected #<paper id: nil, title: "computing machinery and intelligence", venue: nil, year: 1950, created_at: nil, updated_at: nil> not to be valid

25/44 exercise tests have passed

[felixauringer]

fixed in 55a850a89a3290d15765ee14a384ea7b2f386a98