Add missing DEPTH_BIAS_CLAMP and FULL_DRAW_INDEX_UINT32 downlevel flags

[teoxoy]

Checklist

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

Connections

Description
Added missing Vulkan/GLES downlevel flags.
Do note that we don't validate FULL_DRAW_INDEX_UINT32 because we'd have to go through all values in the index buffers and check them.

Testing

[cwfitzgerald]

LGTM minus nit

[codecov-commenter]

Codecov Report

Merging #3316 (e902508) into master (c91cae4) will increase coverage by 0.02%.
The diff coverage is 86.20%.

@@            Coverage Diff             @@
##           master    #3316      +/-   ##
==========================================
+ Coverage   64.28%   64.30%   +0.02%     
==========================================
  Files          83       83              
  Lines       42274    42302      +28     
==========================================
+ Hits        27176    27204      +28     
  Misses      15098    15098              

Impacted Files	Coverage Δ
wgpu-hal/src/dx11/adapter.rs	0.00% <0.00%> (ø)
wgpu-types/src/lib.rs	88.30% <ø> (ø)
wgpu-core/src/device/mod.rs	66.68% <75.00%> (+<0.01%)	⬆️
wgpu-hal/src/gles/adapter.rs	84.07% <100.00%> (+0.11%)	⬆️
wgpu-hal/src/vulkan/adapter.rs	77.77% <100.00%> (+0.26%)	⬆️
wgpu-core/src/hub.rs	60.82% <0.00%> (+0.15%)	⬆️
wgpu-core/src/instance.rs	66.43% <0.00%> (+0.41%)	⬆️

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