Disable "liftShorter" completion classifier on 221 platform

[vlad20012]

LiftShorterItemsClassifier aka "liftShorter" is a completion variants sorter ("classifier") that does a text-based sorting that is hard to explain in words. Let's look at the picture:

Here grayed variants should have been at the end of the list, but they were upped by liftShorter. Why? Well, because they are prefixes of their previous variants! For example, is_equal is a prefix of is_equal_private, so is_equal variant is placed after is_equal_private. Why? Well, I heard that it helps in Java: "liftShorter" places interfaces near their implementations, e.g. places an interface Foo after FooImpl if FooImpl is prioritized for some reason. Why does liftShorter work in all languages by default? I have no idea. We decided to disable liftShorter in Rust because we can't find any Rust naming pattern where it is useful.

How to see "liftShorter" in action:

1. Disable Machine Learning-Assisted completion in File | Settings | Editor | General | Code Completion

struct S;
impl S {
    fn foobar(&self) -> String { todo!() }
    fn foo(&self) -> i32 { todo!() }
    fn zzz(&self) -> String { todo!() }
}

fn main() {
    let a: String = S./*caret*/
}

Here, foobar and zzz should be prioritized over foo because their return types match with the expected type "String". But if "liftShorter" works, it will place foo after foobar:

This PR disables liftShorter in 2022.1 IDEs. I'd like to disable it in all versions, but this can break the ML completion model.

[vlad20012]

bors r+

[bors]

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[vlad20012]

bors r+

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