feat: switch away from parking_lot::Mutex

Switching away from `parking_lot::Mutex` as `std::sync::Mutex` performs
better in all scenarios on both of our targets (linux/windows).

crates/resource_manager/Cargo.toml

@@ -7,7 +7,6 @@ edition = "2021"
 ash.workspace = true
 gpu-allocator.workspace = true
 thiserror.workspace = true
-parking_lot.workspace = true
 tracing.workspace = true
 
 gfx_hal = { path = "../gfx_hal" }