Enhancement (09_strings/strings2.rs): confusing comment

[Andebugulin]

When I was doing rustlings, I got confused in the comment of this code. I will put here the whole rustling since it is not big:

// TODO: Fix the compiler error in the `main` function without changing this function.
fn is_a_color_word(attempt: &str) -> bool {
    attempt == "green" || attempt == "blue" || attempt == "red"
}

fn main() {
    let word = String::from("green"); // Don't change this line.

    if is_a_color_word(word) {
        println!("That is a color word I know!");
    } else {
        println!("That is not a color word I know.");
    }
}

Main confusion cause is the word this. At first I thought that this might relate to main function because it goes right after it being mentioned in the sentence, then I thought that it might mean function that is directly below.

I believe it is possible to completely eliminate the confusion.

---

Suggestion:

• replace this with the actual name of the funciton is_a_color_word

the whole comment would then look like:

// TODO: Fix the compiler error in the `main` function without changing `is_a_color_word` function.

[brambhattabhishek]

/assign