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 !

3 files changed, 4 insertions, 4 deletions

diff --git a/src/doc/rustc/src/platform-support/fuchsia.md b/src/doc/rustc/src/platform-support/fuchsia.md
index 95c242cc161..29e70129a62 100644
--- a/src/doc/rustc/src/platform-support/fuchsia.md
+++ b/src/doc/rustc/src/platform-support/fuchsia.md
@@ -705,7 +705,7 @@ Where `${RUST_SRC_PATH}/install` is the `prefix` set in `config.toml` and
 
 Once our environment is started, we can run our tests using `x.py` as usual. The
 test runner script will run the compiled tests on an emulated Fuchsia device. To
-run the full `src/test/ui` test suite:
+run the full `tests/ui` test suite:
 
 ```sh
 ( \
@@ -713,7 +713,7 @@ run the full `src/test/ui` test suite:
     ./x.py                                                                    \
     --config config.toml                                                      \
     --stage=2                                                                 \
-    test src/test/ui                                                          \
+    test tests/ui                                                             \
     --target x86_64-unknown-fuchsia                                           \
     --run=always --jobs 1                                                     \
     --test-args --target-rustcflags                                           \
diff --git a/src/doc/unstable-book/src/compiler-flags/codegen-backend.md b/src/doc/unstable-book/src/compiler-flags/codegen-backend.md
index 3c0cd32fae1..67634be6993 100644
--- a/src/doc/unstable-book/src/compiler-flags/codegen-backend.md
+++ b/src/doc/unstable-book/src/compiler-flags/codegen-backend.md
@@ -12,7 +12,7 @@ backend. The library must be of crate type `dylib` and must contain a function
 named `__rustc_codegen_backend` with a signature of `fn() -> Box<dyn rustc_codegen_ssa::traits::CodegenBackend>`.
 
 ## Example
-See also the [`hotplug_codegen_backend`](https://github.com/rust-lang/rust/tree/master/src/test/run-make-fulldeps/hotplug_codegen_backend) test
+See also the [`hotplug_codegen_backend`](https://github.com/rust-lang/rust/tree/master/tests/run-make-fulldeps/hotplug_codegen_backend) test
 for a full example.
 
 ```rust,ignore (partial-example)
diff --git a/src/doc/unstable-book/src/language-features/plugin.md b/src/doc/unstable-book/src/language-features/plugin.md
index 56fe9a31bfe..dfbb468d4df 100644
--- a/src/doc/unstable-book/src/language-features/plugin.md
+++ b/src/doc/unstable-book/src/language-features/plugin.md
@@ -33,7 +33,7 @@ of a library.
 Plugins can extend [Rust's lint
 infrastructure](../../reference/attributes/diagnostics.md#lint-check-attributes) with
 additional checks for code style, safety, etc. Now let's write a plugin
-[`lint-plugin-test.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui-fulldeps/auxiliary/lint-plugin-test.rs)
+[`lint-plugin-test.rs`](https://github.com/rust-lang/rust/blob/master/tests/ui-fulldeps/auxiliary/lint-plugin-test.rs)
 that warns about any item named `lintme`.
 
 ```rust,ignore (requires-stage-2)