Contributing: merge testing bullets and include Kselftests

This simplifies things (since the Testing page in the kernel documentation
contains all too) and also means the KUnit `#[test]`s (and not just the
host ones), are covered.

Signed-off-by: Miguel Ojeda <[email protected]>

Author: ojeda

src/Contributing.md

@@ -108,12 +108,10 @@ The following items apply to every patch in a series. That is, in general, each
 
   - When submitting changes to Rust code documentation, please render them using the `rustdoc` target and ensure the result looks as expected. The Rust code documentation gets rendered at <https://rust.docs.kernel.org>.
 
-  - When submitting changes to examples inside Rust code documentation (i.e. "doctests"), which are transformed into KUnit tests, please test them by [running them](https://docs.kernel.org/rust/testing.html).
+  - When submitting changes to tests, including `#[test]`s, Kselftests and examples inside Rust code documentation (i.e. "doctests", which are transformed into KUnit tests), please [test them](https://docs.kernel.org/rust/testing.html).
 
   - When submitting changes to the Rust folder of the kernel documentation (i.e. `Documentation/rust/`), which are written in reStructuredText and handled by Sphinx, please [render them](https://docs.kernel.org/doc-guide/sphinx.html) (typically using the `htmldocs` target) to ensure there are no warnings and that the result looks as expected. The Rust kernel documentation gets rendered at <https://docs.kernel.org/rust/>.
 
-  - When submitting changes to `#[test]`s, please test them by running the `rusttest` target.
-
   - Ideally, please check your changes with both the latest stable Rust compiler as well as the minimum supported version (`scripts/min-tool-version.sh rustc`), including Clippy.
 
 ### Key cycle dates