macos: `anti_aliasing` example crashes when MSAA is set to 8 samples

[rparrett]

Bevy version

main, since #14273

Relevant system information

SystemInfo { os: "MacOS 14.5 ", kernel: "23.5.0", cpu: "Apple M1 Max", core_count: "10", memory: "64.0 GiB" }
AdapterInfo { name: "Apple M1 Max", vendor: 0, device: 0, device_type: IntegratedGpu, driver: "", driver_info: "", backend: Metal }

What you did

1. cargo run --example anti_aliasting
2. Select MSAA
3. Select 8 samples

What went wrong

App crashes

2024-10-09T15:29:05.575172Z ERROR wgpu_core::device::global: Device::create_texture error: Sample count 8 is not supported by format Rgba16Float on this device. The WebGPU spec guarantees [1, 4] samples are supported by this format. With the TEXTURE_ADAPTER_SPECIFIC_FORMAT_FEATURES feature your device supports [1, 2, 4].    
2024-10-09T15:29:05.575243Z ERROR wgpu::backend::wgpu_core: Handling wgpu errors as fatal by default    
thread 'Compute Task Pool (0)' panicked at /Users/me/.cargo/registry/src/index.crates.io-6f17d22bba15001f/wgpu-0.20.1/src/backend/wgpu_core.rs:2996:5:
wgpu error: Validation Error

Caused by:
    In Device::create_texture
      note: label = `main_texture_sampled`
    Sample count 8 is not supported by format Rgba16Float on this device. The WebGPU spec guarantees [1, 4] samples are supported by this format. With the TEXTURE_ADAPTER_SPECIFIC_FORMAT_FEATURES feature your device supports [1, 2, 4].


note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Encountered a panic in system `bevy_render::view::prepare_view_targets`!

Additional information

Before this PR, the app would not crash, and would emit a helpful warning.

2024-10-09T15:28:24.305025Z  WARN bevy_render::view::window: MSAA 8x is not supported on this device. Falling back to MSAA 4x.

[BenjaminBrienen]

I'm investigating how the functionality here might have been moved, and if not, how a fallback can be implemented here.