Update the CI to take the rust-toolchain file into account

.github/workflows/bench-manual.yml

@@ -21,8 +21,6 @@ jobs:
             - uses: actions-rs/toolchain@v1
               with:
                 profile: minimal
-                toolchain: stable
-                override: true
 
             - name: Run benchmarks - workload ${WORKLOAD_NAME} - branch ${{ github.ref }} - commit ${{ github.sha }}
               run: |