cargo: Delete metal-rs patch

This is a library crate, meaning that `[patch]`es don't get applied
when users depend on our crate, and falsely end up with a broken
build while our CI said everything was hunky dory (https://github.com/
/issues/224).  We also cannot have a
direct `git` dependency as that prevents us from publishing to
crates.io.  The current workaround to that is to use a custom registry
for both `metal-rs` and `gpu-allocator` until our upstream changes
are merged and released.

What's worse, the harcoded hash that this was pointing to no longer
has a live reference on our fork (maybe due to a force-push), and the
CI is now failing to to fetch that commit by hash while build-testing
`gpu-allocator`.

Cargo.toml

@@ -96,6 +96,3 @@ metal = ["dep:metal"]
 public-winapi = ["dep:winapi"]
 
 default = ["d3d12", "vulkan"]
-
-[patch.crates-io]
-metal = { git = "https://github.com/Traverse-Research/metal-rs", rev = "a354c33" }

src/vulkan/mod.rs

@@ -105,7 +105,7 @@ pub struct AllocatorCreateDesc {
 /// let my_gpu_data: Vec<MyGpuData> = make_vertex_data();
 /// ```
 ///
-/// Depending on how the data we're copying will be used, the vulkan device may have a minimum
+/// Depending on how the data we're copying will be used, the Vulkan device may have a minimum
 /// alignment requirement for that data:
 ///
 /// ```ignore
@@ -180,7 +180,7 @@ impl Allocation {
     ///
     /// [`Slab`]: presser::Slab
     // best to be explicit where the lifetime is coming from since we're doing unsafe things
-    // and relying on an inferred liftime type in the PhantomData below
+    // and relying on an inferred lifetime type in the PhantomData below
     #[allow(clippy::needless_lifetimes)]
     pub fn try_as_mapped_slab<'a>(&'a mut self) -> Option<MappedAllocationSlab<'a>> {
         let mapped_ptr = self.mapped_ptr()?.cast().as_ptr();