chore: test against node 20

Author: danielroe

.github/workflows/ci.yml

@@ -45,7 +45,7 @@ jobs:
       - run: corepack enable
       - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
         with:
-          node-version: 18
+          node-version: 20
           cache: "pnpm"
 
       - name: 📦 Install dependencies