ci: use pnpm 9 (#28)

* ci: use pnpm 9

* chore: define pnpm version in package.json

Author: hanspagel

.github/workflows/ci.yml

@@ -18,8 +18,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: pnpm/action-setup@v4
-        with:
-          version: 8
       - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v4
         with:

package.json

@@ -14,5 +14,6 @@
     "@changesets/cli": "^2.27.1",
     "turbo": "^1.11.1",
     "typescript": "^5.2.2"
-  }
+  },
+  "packageManager": "pnpm@9.2.0"
 }