chore: fix node version

Author: Andrea Aramini, INI-MBM-BNC (EXT)

.github/workflows/main.yml

@@ -10,9 +10,9 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - name: Setup Node.js
-        uses: actions/setup-node@v1
+        uses: actions/setup-node@v3
         with:
-          node-version: 12
+          node-version: 21
       - name: Install dependencies
         run: npm install
       - name: Check indentation