Re-export Naga

[exrook]

Checklist

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

Connections
Fixes #3559

Description
Allow users to use the same version of Naga wgpu is using.

Allows the wgpu::ShaderSource::Naga and wgpu::ShaderSource::Glsl apis to be used without the user having to manually match their own naga dependency version to that of wgpu.

Testing
n/a

[jimblandy]

This looks good. At first I thought it was overkill for just the shader stage and the hash table type, but people also need the right Naga if they want to use ShaderSource::Naga, so this is probably inevitable.

[jimblandy]

@exrook I've enabled CI for this PR - could you take a look at the failures?

[exrook]

@jimblandy Just rustfmt wanting the use statements in alphabetical order, fixed 👍