Rollup merge of rust-lang#140673 - GuillaumeGomez:clean-rustdoc-tests, r=notriddle

Clean rustdoc tests folder

We were starting to have way too many tests in the `tests/rustdoc/` folder so I moved some of them in sub-folders. We now have less than 300 tests at the "top level" so I guess it's good enough for now.

So this PR just moves tests in sub-folders and that's pretty much it. 😃

r? `@notriddle`

Author: Zalathar

tests/rustdoc/anchor-id-duplicate-method-name-25001.rs renamed to tests/rustdoc/anchors/anchor-id-duplicate-method-name-25001.rs

@@ -0,0 +1 @@
+// intentionally empty

tests/rustdoc/anchor-id-trait-method-15169.rs renamed to tests/rustdoc/anchors/anchor-id-trait-method-15169.rs

@@ -0,0 +1,5 @@
+pub enum Foo {
+    Bar {
+        qux: (),
+    }
+}

tests/rustdoc/anchor-id-trait-tymethod-28478.rs renamed to tests/rustdoc/anchors/anchor-id-trait-tymethod-28478.rs

@@ -0,0 +1,20 @@
+pub struct Option;
+impl Option {
+    pub fn unwrap(self) {}
+}
+
+mod macros {
+    use crate::Option;
+    /// [`Option::unwrap`]
+    #[macro_export]
+    macro_rules! print {
+        () => ()
+    }
+}
+
+mod structs {
+    use crate::Option;
+    /// [`Option::unwrap`]
+    pub struct Print;
+}
+pub use structs::Print;

tests/rustdoc/anchors.no_const_anchor.html renamed to tests/rustdoc/anchors/anchors.no_const_anchor.html

@@ -0,0 +1,22 @@
+#![feature(extern_types)]
+
+pub mod foo_mod {}
+extern "C" {
+    pub fn foo_ffn();
+    pub static FOO_FSTATIC: FooStruct;
+    pub type FooFType;
+}
+pub fn foo_fn() {}
+pub trait FooTrait {}
+pub struct FooStruct;
+pub enum FooEnum {}
+pub union FooUnion {
+    x: (),
+}
+pub type FooType = FooStruct;
+pub static FOO_STATIC: FooStruct = FooStruct;
+pub const FOO_CONSTANT: FooStruct = FooStruct;
+#[macro_export]
+macro_rules! foo_macro {
+    () => ();
+}