Only save cache for std

Author: object-Object

.github/workflows/ci.yml

@@ -24,6 +24,8 @@ jobs:
           submodules: true
 
       - uses: Swatinem/rust-cache@v2
+        with:
+          save-if: ${{ matrix.features == 'std' }}
 
       - name: Run tests
         run: cargo test --no-default-features --features ${{ matrix.features }}