CI: Install toolchain in one step

Instead of two steps installing the toolchain, do it one step.
Removes the unmaintained action-rs/toolchain action.
Installs stable clippy instead of nightly clippy.

.github/workflows/cbindgen.yml

@@ -17,22 +17,17 @@ jobs:
  - uses: actions/checkout@v2
 
  - name: Install stable
- uses: actions-rs/toolchain@v1
+ uses: dtolnay/rust-toolchain
  with:
- profile: minimal
  toolchain: stable
- override: true
- components: rustfmt
+ components: "clippy, rustfmt"
 
  - name: Run rustfmt
  uses: actions-rs/cargo@v1
  with:
  command: fmt
  args: -- --check
 
- - name: Install clippy
- uses: dtolnay/rust-toolchain@clippy
-
  - name: Run clippy
  run: |
  cargo clippy --workspace -- -D warnings