ci: add and use lts/iron (Node.js 20 LTS)

Author: panva

.github/workflows/release.yml

@@ -17,7 +17,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v4
         with:
-          node-version: lts/hydrogen # 18
+          node-version: lts/iron # 20
           registry-url: https://registry.npmjs.org
           always-auth: true
       - run: npm publish --provenance
@@ -50,7 +50,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v4
         with:
-          node-version: lts/hydrogen # 18
+          node-version: lts/iron # 20
           cache: 'npm'
       - run: node .release-notes.cjs
         env:

.github/workflows/test.yml

@@ -18,7 +18,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v4
         with:
-          node-version: lts/hydrogen # 18
+          node-version: lts/iron # 20
           cache: 'npm'
       - run: npm clean-install
       - run: npm run format-check
@@ -31,7 +31,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v4
         with:
-          node-version: lts/hydrogen # 18
+          node-version: lts/iron # 20
           cache: 'npm'
       - run: npm clean-install
       - run: npm run test-types
@@ -43,6 +43,7 @@ jobs:
         node-version:
           - lts/gallium # 16
           - lts/hydrogen # 18
+          - lts/iron # 20
           - current
     steps:
       - uses: actions/checkout@v4