Application closing in react_ui and 3d_scene examples impacts webviews visibility.

[MaksymSharinDev]

bevy_webview version

The commit hash of the version you're using.

4b8abd1

Bevy version

The release number of the version you're using.

0.9.0

Operating system & version

Ubuntu 20.04.1

What you did

The steps you took to uncover this bug. Please list full reproduction steps if
feasible.

1. running RUST_LOG="bevy_webview=debug,warn,info,error" cargo run --example react_ui
2. the Webview are visible
3. close the window
4. running RUST_LOG="bevy_webview=debug,warn,info,error" cargo run --example react_ui
5. the Webview are invisible
6. Ctrl+C on terminal to stop the runtime
7. running 4. running RUST_LOG="bevy_webview=debug,warn,info,error" cargo run --example react_ui
8. the Webview are visible again

What you expected to happen

when closing the window and re-running the example the visibility should be consistent as the program was closed by Ctrl+C on the terminal

Additional information

A video illustrating the misbehavior:

Peek.2023-02-25.23-30.mp4

Discovered during:

#12

[MaksymSharinDev]

fixed by 217429d