bevy_window: fix compilation without default features (#19870)
# Objective
- bevy_window fails to compile without default features
```
error: cannot find derive macro `Reflect` in this scope
--> crates/bevy_window/src/window.rs:1474:60
|
1474 | #[derive(Default, Debug, Clone, Copy, PartialEq, Eq, Hash, Reflect)]
| ^^^^^^^
warning: unused import: `format`
--> crates/bevy_window/src/window.rs:1:30
|
1 | use alloc::{borrow::ToOwned, format, string::String};
| ^^^^^^
|
= note: `#[warn(unused_imports)]` on by default
warning: `bevy_window` (lib) generated 1 warning
error: could not compile `bevy_window` (lib) due to 1 previous error; 1 warning emitted
```
## Solution
- Fix them
## Testing
`cargo build -p bevy_window --no-default-features --features
bevy_math/libm`
bcb5520742