ci(cargo-sort): check formatting and item order of Cargo.toml files

.github/workflows/main.yml

@@ -98,6 +98,29 @@ jobs:
     - name: "rustdoc generation check"
       run: cargo rustdoc -p riot-rs-embassy -- -D warnings
 
+  cargo-sort:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Check out repository code
+      uses: actions/checkout@v4
+
+    - name: Install toolchain
+      uses: dtolnay/rust-toolchain@nightly
+
+    - name: rust cache
+      uses: Swatinem/rust-cache@v2
+
+    # The compiled binary should be cached.
+    # rust-sort does provide binary releases but the last release is outdated
+    # and buggy so we compile a more recent version ourselves.
+    # TODO: use the binary release if one gets published later
+    - name: Install rust-sort
+      run: cargo install --git=https://github.com/DevinR528/cargo-sort --rev 55ec89082466f6bb246d870a8d56d166a8e1f08b cargo-sort
+
+    - name: Check formatting and item order of Cargo.toml files
+      run: cargo sort --check --check-format --grouped --workspace
+
   CI-success:
       if: ${{ always() }}
       runs-on: ubuntu-latest