ci: fix self-hosted rust ci. (#50)

Author: lshqqytiger

.github/workflows/pr_rust.yml

@@ -11,7 +11,6 @@ jobs:
       run:
         working-directory: ./test
     steps:
-      - uses: actions-rust-lang/setup-rust-toolchain@v1
       - uses: actions/checkout@v4
         with:
           submodules: true