ci: use rust-toolchain to sync rust version between local and ci operations

Author: alukach

.github/workflows/ci.yaml

@@ -10,9 +10,7 @@ jobs:
     steps:
       - uses: actions/checkout@d632683dd7b4114ad314bca15554477dd762a938 # v4.2.0
       - name: Set up Rust
-        uses: actions-rs/toolchain@8e603f32c5c6eeca5b1b2d9d1e7464d926082f1d # v1.0.0
-        with:
-          toolchain: stable
+        run: rustup show
       - name: Format
         run: cargo fmt --check
       - name: Clippy

rust-toolchain.toml

@@ -0,0 +1,2 @@
+[toolchain]
+channel = "stable"