Unclear and inconsistent function used in test_flight_interventions.jl

[TheHelenofTroy]

In tests/test_flight_interventions.jl, the function model_ingredients_from_data is called multiple times, but none of which matches any of the two functions named model_ingredients_from_data in src/transmissionmodel.jl on https://github.com/SamuelBrand1/KenyaCoV/blob/master/src/transmissionmodel.jl#L66 and https://github.com/SamuelBrand1/KenyaCoV/blob/master/src/transmissionmodel.jl#L101.

The function in the test script has a float type argument, and neither function in the source specifies a float type argument. Based on naming convention, both functions with the same name model_ingredients_from_data are calling for string type arguments.

Julia throws MethodError and LoadError for this test script when the function is called.