Move /src/test to /tests

tests/rustdoc-ui/test-no_std.rs

@@ -0,0 +1,13 @@
+// compile-flags:--test
+// normalize-stdout-test: "src/test/rustdoc-ui" -> "$$DIR"
+// normalize-stdout-test "finished in \d+\.\d+s" -> "finished in $$TIME"
+// check-pass
+
+#![no_std]
+
+extern crate alloc;
+
+/// ```
+/// assert!(true)
+/// ```
+pub fn f() {}