SUMMARY: move "Documentation" a bit higher

Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Author: ojeda

SUMMARY.md

@@ -55,6 +55,14 @@
   - [Unstable features](https://github.com/Rust-for-Linux/linux/issues/2)
   - [Good first issues](https://github.com/Rust-for-Linux/linux/contribute)
 
+## Documentation
+
+  - [Kernel documentation (mainline)](https://docs.kernel.org/rust/)
+  - [Kernel documentation (next)](https://docs.kernel.org/next/rust/)
+  - [`rustdoc` code docs (v6.8)](https://rust-for-linux.github.io/docs/v6.8/kernel/)
+  - [`rustdoc` code docs (`rust` 2023-03-13)](https://rust-for-linux.github.io/docs/rust/kernel/)
+  - [Out-of-tree module template](https://github.com/Rust-for-Linux/rust-out-of-tree-module)
+
 ## Main branches
 
   - [`rust-next`](https://github.com/Rust-for-Linux/linux/tree/rust-next)
@@ -68,14 +76,6 @@
   - [`staging/rust-device`](https://github.com/Rust-for-Linux/linux/tree/staging/rust-device)
   - [`staging/dev`](https://github.com/Rust-for-Linux/linux/tree/staging/dev)
 
-## Documentation
-
-  - [Kernel documentation (mainline)](https://docs.kernel.org/rust/)
-  - [Kernel documentation (next)](https://docs.kernel.org/next/rust/)
-  - [`rustdoc` code docs (v6.8)](https://rust-for-linux.github.io/docs/v6.8/kernel/)
-  - [`rustdoc` code docs (`rust` 2023-03-13)](https://rust-for-linux.github.io/docs/rust/kernel/)
-  - [Out-of-tree module template](https://github.com/Rust-for-Linux/rust-out-of-tree-module)
-
 ## Conferences
 
   - [Kangrejos](https://kangrejos.com)