[github workflow] update pnpm version to 8

.github/workflows/build-test.yml

@@ -12,15 +12,15 @@ jobs:
         node-version: [16]
 
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v4
       - name: Use Node.js ${{ matrix.node-version }}
-        uses: actions/setup-node@v1
+        uses: actions/setup-node@v4
         with:
           node-version: ${{ matrix.node-version }}
       - name: Install pnpm
-        uses: pnpm/action-setup@v2
+        uses: pnpm/action-setup@v4
         with:
-          version: 7
+          version: 8
       - name: Install, build and test
         timeout-minutes: 5
         run: |