Upgrade dependencies and cache yarn

Author: MisRob

.github/workflows/manage-issue-header.yml

@@ -27,24 +27,25 @@ jobs:
           private_key: ${{ secrets.LE_BOT_PRIVATE_KEY }}
 
       - name: Checkout .github repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: MisRob/.github
           ref: issue-header-action
           token: ${{ steps.generate-token.outputs.token }}
-      
+
       - name: Setup Node.js
-        uses: actions/setup-node@v3
+        uses: actions/setup-node@v4
         with:
-          node-version: '16'
+          node-version: 20
+          cache: 'yarn'
 
       - name: Install dependencies
-        run: npm install 
+        run: yarn install --frozen-lockfile
 
       - name: Run script
-        uses: actions/github-script@v6
+        uses: actions/github-script@v7
         with:
           github-token: ${{ steps.generate-token.outputs.token }}
           script: |
             const script = require('./scripts/manage-issue-header.js');
-            return await script({github, context, core});
+            await script({github, context, core});