a warning tip

warning: fields `key_placeholder`, `value_placeholder`, and `state_placeholder` are never read
  --> C:\Users\dongl\Desktop\projects\gameProject\Fyrox\fyrox-ui\src\inspector\editors\hashmap\mod.rs:69:5
   |
63 | pub struct HashMapPropertyEditorDefinition<K, V, S>
   |            ------------------------------- fields in this struct
...
69 |     key_placeholder: PhantomDataSendSync<K>,
   |     ^^^^^^^^^^^^^^^
70 |     value_placeholder: PhantomDataSendSync<V>,
   |     ^^^^^^^^^^^^^^^^^
71 |     state_placeholder: PhantomDataSendSync<S>,
   |     ^^^^^^^^^^^^^^^^^
   |
   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default

warning: `fyrox-ui` (lib) generated 1 warning
warning: variable does not need to be mutable
  --> game\src\lib.rs:44:51
   |
44 |     fn init(&mut self, _scene_path: Option<&str>, mut context: PluginContext) -> GameResult {
   |                                                   ----^^^^^^^
   |                                                   |
   |                                                   help: remove this `mut`
   |
   = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default

warning: `game` (lib) generated 1 warning (run `cargo fix --lib -p game` to apply 1 suggestion)