update gpu-allocator to 0.23

[Elabajaba]

Checklist

• Run cargo clippy.
• Run cargo clippy --target wasm32-unknown-unknown if applicable.
• Add change to CHANGELOG.md. See simple instructions inside file.

Description
Bump gpu-allocator to 0.23.

This also means we can expose an api to set allocator sizes for end users for both dx12 and vulkan (though the vulkan ones for gpu-alloc are imo quite confusing, and the dx12 one only exposes static sizes for block size).

Testing
I ran the boids example and it still worked.