ci: update to pnpm 7

Author: juanrgm

.github/workflows/ci.yaml

@@ -25,7 +25,7 @@ jobs:
       - name: Use pnpm
         uses: pnpm/action-setup@v2
         with:
-          version: 6
+          version: 7
       - name: Setup pnpm config
         run: pnpm config set store-dir $PNPM_CACHE_FOLDER
       - name: Install dependencies