Auto merge of #106458 - albertlarsan68:move-tests, r=jyn514

Move src/test to the root

See MCP at rust-lang/compiler-team#573

There may be more changes needed.

The first commit is just the move of the files:
You can check that the first commit did not do anything else than renames by running
```
git diff --diff-filter=r -M100% <rust-lang remote>/master <first commit hash>
```
The output should be empty, because the filter excludes renames, and the match threshold for qualifying a rename is 100%.

The second one is mostly a "find and replace" of `src/test` to `tests` and whatever is needed to make CI pass.

What is left to do:
---

- [x] Move directory
- [ ] Change references to `src/test`
    - [x] Change references in-tree
    - [ ] Change references in submodules / out-of-tree docs
- [x] Make CI pass:
    - [x] Fix tidy
    - [x] Fix tests
    - [x] Bless tests if needed (shouldn't normally)
- [ ] Merge it !

1 files changed, 17 insertions, 0 deletions

diff --git a/tests/rustdoc/const-generics/add-impl.rs b/tests/rustdoc/const-generics/add-impl.rs
new file mode 100644
index 00000000000..6cbae9abebb
--- /dev/null
+++ b/tests/rustdoc/const-generics/add-impl.rs
@@ -0,0 +1,17 @@
+#![crate_name = "foo"]
+
+use std::ops::Add;
+
+// @has foo/struct.Simd.html '//pre[@class="rust struct"]' 'pub struct Simd<T, const WIDTH: usize>'
+pub struct Simd<T, const WIDTH: usize> {
+    inner: T,
+}
+
+// @has foo/struct.Simd.html '//div[@id="trait-implementations-list"]//h3[@class="code-header"]' 'impl Add<Simd<u8, 16>> for Simd<u8, 16>'
+impl Add for Simd<u8, 16> {
+    type Output = Self;
+
+    fn add(self, rhs: Self) -> Self::Output {
+        Self { inner: 0 }
+    }
+}