chore(ci): Check clippy warning

Author: tottoto

.github/workflows/CI.yml

@@ -38,8 +38,6 @@ jobs:
     - uses: taiki-e/install-action@protoc
     - uses: Swatinem/rust-cache@v2
     - run: cargo clippy --workspace --all-features --all-targets
-      env:
-        RUSTFLAGS: "-A warnings"
 
   codegen:
     runs-on: ubuntu-latest