ci: Downgrade to Node.js 16

To hopefully fix the build issues

Node.js 20 and 18 don't work. Partially due to angular/angular-cli#25782

Author: maxpatiiuk

.github/workflows/build.yaml

@@ -16,7 +16,7 @@ jobs:
       - name: Set up Node.js
         uses: actions/setup-node@v3
         with:
-          node-version: '20'
+          node-version: '16'
 
       - name: Install dependencies
         run: npm ci