Move /src/test to /tests

tests/rustdoc/async-trait.rs

@@ -0,0 +1,16 @@
+// aux-build:async-trait-dep.rs
+// edition:2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+extern crate async_trait_dep;
+
+pub struct Oink {}
+
+// @has 'async_trait/struct.Oink.html' '//h4[@class="code-header"]' "async fn woof()"
+impl async_trait_dep::Meow for Oink {
+    async fn woof() {
+        todo!()
+    }
+}