Add rustfmt component

Author: CuteChuanChuan

.github/workflows/rust.yml

@@ -629,7 +629,7 @@ jobs:
           echo '' > datafusion/proto/src/generated/datafusion.rs
           ci/scripts/rust_fmt.sh
       - name: Setup nightly Rust toolchain
-        run: rustup toolchain install nightly
+        run: rustup toolchain install nightly --component rustfmt
       - name: Check doc comment code formatting
         run: cargo +nightly fmt --all -- --check --config format_code_in_doc_comments=true