chore: pnpm to v8 for CI

Author: baboon-king

.github/workflows/ci.yml

@@ -28,7 +28,7 @@ jobs:
       - uses: actions/checkout@v1
       - uses: pnpm/[email protected]
         with:
-          version: 6
+          version: 8
       - uses: actions/setup-node@v2
         with:
           node-version: ${{ matrix.node-version }}