Remove stale referenece to rust-toolchain removed in apache#1383, surpised pre-commit didn't flag for anyone else

Author: ntjohnson1

.github/workflows/test.yaml

@@ -77,7 +77,7 @@ jobs:
         uses: actions/cache@v5
         with:
           path: ~/.cargo
-          key: cargo-cache-${{ steps.rust-toolchain.outputs.cachekey }}-${{ hashFiles('Cargo.lock') }}
+          key: cargo-cache-${{ matrix.toolchain }}-${{ hashFiles('Cargo.lock') }}
 
       - name: Run Clippy
         if: ${{ matrix.python-version == '3.10' && matrix.toolchain == 'stable' }}
@@ -93,9 +93,7 @@ jobs:
           RUST_BACKTRACE: 1
         run: |
           git submodule update --init
-          uv sync --dev --no-install-package datafusion
-          uv run --no-project maturin develop --uv
-          uv run --no-project pytest -v .
+          uv run --no-project pytest -v --import-mode=importlib
 
       - name: FFI unit tests
         run: |