Update GH Actions to use Node 20.

Author: Fyorl

.github/workflows/npm-publish-github-packages.yml

@@ -11,10 +11,10 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
-      - uses: actions/setup-node@v3
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
         with:
-          node-version: 16
+          node-version: 20
       - run: npm ci
 
   publish-gpr:
@@ -24,10 +24,10 @@ jobs:
       contents: read
       packages: write
     steps:
-      - uses: actions/checkout@v3
-      - uses: actions/setup-node@v3
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
         with:
-          node-version: 16
+          node-version: 20
           registry-url: https://registry.npmjs.org
       - run: npm ci
       - run: git config --global user.email "andrew@foundryvtt.com"