ci: Add missing component

Author: udoprog

.github/workflows/ci.yml

@@ -44,7 +44,7 @@ jobs:
     - uses: actions/checkout@v4
     - uses: dtolnay/rust-toolchain@stable
       with:
-        components: clippy
+        components: rustfmt
     - run: cargo fmt --check --all
 
   docs: