Update publish workflow to use node 18

.github/workflows/publish.yaml

@@ -12,7 +12,7 @@ jobs:
     # Setup .npmrc file to publish to npm
     - uses: actions/setup-node@v1
       with:
-        node-version: '12.x'
+        node-version: '18.x'
         registry-url: 'https://registry.npmjs.org'
     - run: npm ci
     - run: npm run compile