Migrate to parking_lot

src/selector.rs

@@ -15,7 +15,8 @@ use iced::{Element, Task, alignment};
 use iced_core::Alignment::Center;
 use iced_core::Background;
 use iced_core::Color;
-use std::sync::{Arc, Mutex};
+use std::sync::Arc;
+use parking_lot::Mutex;
 
 pub struct SelectorState {
     pub set: KanaSet,