C# tests generate warnings:

tests/Fixture.cs(41,31): warning CS0168: The variable 'e' is declared but never used
tests/Fixture.cs(56,31): warning CS0168: The variable 'e' is declared but never used
tests/Fixture.cs(71,31): warning CS0168: The variable 'e' is declared but never used
tests/Fixture.cs(86,31): warning CS0168: The variable 'e' is declared but never used

Ruby 3.0 should be enabled, read this to learn how to do it

Please organize the structure of test fixture as following (although it has been mentioned in the attached link, I'm repeated here again)

describe "<This message should describe the categories of test groups inside this block>" do
  it "<A short message describing this test group>" do
    expect(...).to eq(...) #Assertions
    #Or Test.assert_equals(user_response, reference_response)
  end
end