Vendor dependencies

Let's see how I like this workflow.

vendor/pin-project-lite/tests/ui/pinned_drop/call-drop-inner.stderr

@@ -0,0 +1,22 @@
+error[E0061]: this function takes 0 arguments but 1 argument was supplied
+  --> tests/ui/pinned_drop/call-drop-inner.rs:10:13
+   |
+10 |             __drop_inner(this);
+   |             ^^^^^^^^^^^^ ---- argument unexpected
+   |
+note: function defined here
+  --> tests/ui/pinned_drop/call-drop-inner.rs:3:1
+   |
+3  | / pin_project! {
+4  | |     pub struct S {
+5  | |         #[pin]
+6  | |         field: u8,
+...  |
+12 | |     }
+13 | | }
+   | |_^
+   = note: this error originates in the macro `$crate::__pin_project_make_drop_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: remove the extra argument
+   |
+10 |             __drop_inner();
+   |             ~~~~~~~~~~~~~~