Update publish.yml

Author: muhammadsammy

.github/workflows/publish.yml

@@ -13,7 +13,7 @@ jobs:
 
             - uses: actions/setup-node@v1
               with:
-                  node-version: 10
+                  node-version: '15.x'
 
             - run: npm ci
             - run: npm install -g gulp ovsx