Update Node version in release

Author: mheap

.github/workflows/release.yml

@@ -10,10 +10,10 @@ jobs:
     - uses: actions/checkout@v2
       with:
         ref: ${{ github.event.release.target_commitish }}
-    - name: Use Node.js 12
+    - name: Use Node.js 18
       uses: actions/setup-node@v1
       with:
-        node-version: 12
+        node-version: 18
         registry-url: https://registry.npmjs.org/
     - run: npm ci
     - run: git config --global user.name "Michael Heap"