Decrease max_buffer_size limit value to be compatible with Apple2 GPU

[jinleili]

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
From matrix: max_buffer_size: 1<<30 is larger than Apple2 GPU's limits

Description

Testing
Tested locally on Apple2 GPU device (iPhone 6)

[codecov-commenter]

Codecov Report

Merging #3255 (291d732) into master (88acaf7) will decrease coverage by 18.46%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           master    #3255       +/-   ##
===========================================
- Coverage   65.60%   47.13%   -18.47%     
===========================================
  Files          82       82               
  Lines       39468    39439       -29     
===========================================
- Hits        25894    18591     -7303     
- Misses      13574    20848     +7274     

Impacted Files	Coverage Δ
wgpu-types/src/lib.rs	85.51% <100.00%> (-2.62%)	⬇️
wgpu-hal/src/gles/device.rs	0.00% <0.00%> (-80.19%)	⬇️
wgpu-hal/src/vulkan/adapter.rs	0.00% <0.00%> (-77.52%)	⬇️
wgpu-hal/src/vulkan/device.rs	0.00% <0.00%> (-75.42%)	⬇️
wgpu-hal/src/gles/conv.rs	0.00% <0.00%> (-74.36%)	⬇️
wgpu-hal/src/gles/adapter.rs	9.70% <0.00%> (-73.90%)	⬇️
wgpu-hal/src/vulkan/conv.rs	1.11% <0.00%> (-70.66%)	⬇️
wgpu-hal/src/gles/command.rs	0.00% <0.00%> (-69.83%)	⬇️
wgpu-hal/src/vulkan/command.rs	0.92% <0.00%> (-67.42%)	⬇️
wgpu-hal/src/gles/mod.rs	0.00% <0.00%> (-61.54%)	⬇️
... and 13 more

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

[cwfitzgerald]

For reference, this is the value in the spec too.

[cwfitzgerald]

This is an implicit change, so should likely be front and center in the changelog