Better test for exercises/10_modules/modules1.rs

[Anu-Ra-g]

In this exercise, if we comment out the function call in the main function, the test passes,

fn main() {
    // sausage_factory::make_sausage();
}

I'm suggesting to add a better test for this exercise. So that on commenting the testcase we don't pass the test case.

[JiwaniZakir]

I'll handle this.