Drop actions-rs/toolchain usage from publish workflow

Similar to what we did for the test GitHub Action workflow, replace the
deprecated actions-rs/toolchain with dtolnay/rust-toolchain.

.github/workflows/publish.yml

@@ -38,12 +38,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3
-    - name: Install Rust
-      uses: actions-rs/toolchain@v1
-      with:
-        profile: minimal
-        toolchain: stable
-        override: true
+    - uses: dtolnay/rust-toolchain@stable
     - name: Dry-run package creation
       run: cargo package --no-verify
     - name: Create git tag