Use objc2-metal with metal naming scheme

To keep the diff smaller and easier to review, this uses a temporary
fork of `objc2-metal` and `objc2-quartz-core` whose methods use the
naming scheme of the `metal` crate.

One particular difficult part with this is that the `metal` crate has
several methods where the order of the arguments are swapped relative
to the corresponding Objective-C methods.

This includes most perilously the following, since these have both an
offset and an index argument, both of which are integers:
- `set_bytes`
- `set_vertex_bytes`
- `set_fragment_bytes`
- `set_buffer`
- `set_vertex_buffer`
- `set_fragment_buffer`
- `set_threadgroup_memory_length`

But also:
- `set_vertex_texture`
- `set_fragment_texture`
- `set_sampler_state`
- `set_vertex_sampler_state`
- `set_fragment_sampler_state`

Author: madsmtm

CHANGELOG.md

@@ -818,6 +818,9 @@ By @cwfitzgerald in [#6811](https://github.com/gfx-rs/wgpu/pull/6811), [#6815](h
 - Move incrementation of `Device::last_acceleration_structure_build_command_index` into queue submit. By @Vecvec in [#7462](https://github.com/gfx-rs/wgpu/pull/7462).
 - Implement indirect draw validation. By @teoxoy in [#7140](https://github.com/gfx-rs/wgpu/pull/7140)
 
+#### Metal
+- Use autogenerated `objc2` bindings internally, which should resolve a lot of leaks and unsoundness. By @madsmtm in [#5641](https://github.com/gfx-rs/wgpu/pull/5641).
+
 #### Vulkan
 
 - Stop naga causing undefined behavior when a ray query misses. By @Vecvec in [#6752](https://github.com/gfx-rs/wgpu/pull/6752).