fix: handle guards in replace_if_let_with_match

[A4-Tacks]

• Support let-chain to guard
• Fix loses comments
• Fix bad indentation

Example

fn main() {
    if $0let true = true
        && true
        && false
    {
        code()
    }
}

Before this PR

Assist not applicable

After this PR

fn main() {
    match true {
        true if true
            && false => code(),
        _ => (),
    }
}

---

pub fn foo(foo: i32) {
    $0if let 1 = foo {
        // some comment
        self.foo();
    } else if let 2 = foo {
        // some comment 2
        self.bar()
    }
}

Before this PR

pub fn foo(foo: i32) {
    match foo {
        1 => {
            self.foo();
        }
        2 => self.bar(),
        _ => (),
    }
}

After this PR

pub fn foo(foo: i32) {
    match foo {
        1 => {
            // some comment
            self.foo();
        }
        2 => {
            // some comment 2
            self.bar()
        },
        _ => (),
    }
}

[A4-Tacks]

r? @ShoyuVanilla