Fix false positive with `missing_docs` and `#[test]`

Since rust-lang#130025, the compiler don't ignore missing_docs when compiling the tests. But there is now a false positive warning for every `#[test]`

For example, this code
```rust
//! Crate docs

fn just_a_test() {}
```

Would emit this warning when running `cargo test`

```
warning: missing documentation for a constant
 --> src/lib.rs:5:1
  |
4 | #[test]
  | ------- in this procedural macro expansion
5 | fn just_a_test() {}
  | ^^^^^^^^^^^^^^^^^^^
```

…kingjubilee

Rollup of 14 pull requests

Successful merges:

 - rust-lang#129260 (Don't suggest adding return type for closures with default return type)
 - rust-lang#129520 (Suggest the correct pattern syntax on usage of unit variant pattern for a struct variant)
 - rust-lang#129696 (update stdarch)
 - rust-lang#129759 (Stabilize `const_refs_to_static`)
 - rust-lang#129835 (enable const-float-classify test, and test_next_up/down on 32bit x86)
 - rust-lang#129866 (Clarify documentation labelling and definitions for std::collections)
 - rust-lang#130052 (Don't leave debug locations for constants sitting on the builder indefinitely)
 - rust-lang#130077 (Fix linking error when compiling for 32-bit watchOS)
 - rust-lang#130123 (Report the `note` when specified in `diagnostic::on_unimplemented`)
 - rust-lang#130156 (Add test for S_OBJNAME & update test for LF_BUILDINFO cl and cmd)
 - rust-lang#130206 (Map `WSAEDQUOT` to `ErrorKind::FilesystemQuotaExceeded`)
 - rust-lang#130207 (Map `ERROR_CANT_RESOLVE_FILENAME` to `ErrorKind::FilesystemLoop`)
 - rust-lang#130219 (Fix false positive with `missing_docs` and `#[test]`)
 - rust-lang#130221 (Make SearchPath::new public)

r? `@ghost`
`@rustbot` modify labels: rollup

…iaskrgr

Rollup of 9 pull requests

Successful merges:

 - rust-lang#129260 (Don't suggest adding return type for closures with default return type)
 - rust-lang#129520 (Suggest the correct pattern syntax on usage of unit variant pattern for a struct variant)
 - rust-lang#129866 (Clarify documentation labelling and definitions for std::collections)
 - rust-lang#130123 (Report the `note` when specified in `diagnostic::on_unimplemented`)
 - rust-lang#130161 (refactor merge base logic and fix `x fmt`)
 - rust-lang#130206 (Map `WSAEDQUOT` to `ErrorKind::FilesystemQuotaExceeded`)
 - rust-lang#130207 (Map `ERROR_CANT_RESOLVE_FILENAME` to `ErrorKind::FilesystemLoop`)
 - rust-lang#130219 (Fix false positive with `missing_docs` and `#[test]`)
 - rust-lang#130221 (Make SearchPath::new public)

r? `@ghost`
`@rustbot` modify labels: rollup

Rollup merge of rust-lang#130219 - ogoffart:missing-docs-test, r=Urgau

Fix false positive with `missing_docs` and `#[test]`

Since rust-lang#130025, the compiler don't ignore missing_docs when compiling the tests. But there is now a false positive warning for every `#[test]`

For example, this code
```rust
//! Crate docs

fn just_a_test() {}
```

Would emit this warning when running `cargo test`

```
warning: missing documentation for a constant
 --> src/lib.rs:5:1
  |
4 | #[test]
  | ------- in this procedural macro expansion
5 | fn just_a_test() {}
  | ^^^^^^^^^^^^^^^^^^^
```