feat: upgrade CI workflows to Node.js 20 (#18)

Author: Copilot

.github/workflows/build.yml

@@ -54,7 +54,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v3
         with:
-          node-version: 16
+          node-version: 20
 
       - name: Fetch Previous version
         id: get-previous-tag

.github/workflows/ci.yml

@@ -33,6 +33,10 @@ jobs:
     steps:
 
       - uses: actions/checkout@v2
+      - name: Setup Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: 20
       - name: Run semantic-release
         if: github.repository == 'casbin/zap-logger' && github.event_name == 'push'
         run: |