fix: use literal rust-toolchain version to fix invalid syntax

Author: nabil-Tounarti

.github/workflows/rust-build.yml

@@ -35,7 +35,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Install Rust toolchain
-        uses: dtolnay/rust-toolchain@${{ inputs.rust-version }}
+        uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: ${{ inputs.rust-version }}
           components: clippy, rustfmt