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, 32 insertions, 0 deletions

diff --git a/tests/ui/use-nested-groups.rs b/tests/ui/use-nested-groups.rs
new file mode 100644
index 00000000000..5c739709e9e
--- /dev/null
+++ b/tests/ui/use-nested-groups.rs
@@ -0,0 +1,32 @@
+// run-pass
+
+mod a {
+    pub enum B {}
+
+    pub mod d {
+        pub enum E {}
+        pub enum F {}
+
+        pub mod g {
+            pub enum H {}
+            pub enum I {}
+        }
+    }
+}
+
+// Test every possible part of the syntax
+use a::{B, d::{self, *, g::H}};
+
+// Test a more common use case
+use std::sync::{Arc, atomic::{AtomicBool, Ordering}};
+
+fn main() {
+    let _: B;
+    let _: E;
+    let _: F;
+    let _: H;
+    let _: d::g::I;
+
+    let _: Arc<AtomicBool>;
+    let _: Ordering;
+}