Use Node.js 20 in CI

.github/workflows/ci.yaml

@@ -11,7 +11,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3
         with:
-          node-version: 18
+          node-version: 20
       - run: npm ci
       - run: npx eslint .
 
@@ -21,7 +21,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3
         with:
-          node-version: 18
+          node-version: 20
       - run: npm ci
       - run: npm pack
       - uses: actions/upload-artifact@v3
@@ -35,7 +35,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3
         with:
-          node-version: 18
+          node-version: 20
       - run: npm ci
       - run: npx remark --frail .
 
@@ -59,15 +59,15 @@ jobs:
           name: test-results-node${{ matrix.node-version }}
           path: test-results/
       - uses: codecov/codecov-action@v3
-        if: ${{ matrix.node-version == 18 }}
+        if: ${{ matrix.node-version == 20 }}
 
   prettier:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v1
       - uses: actions/setup-node@v1
         with:
-          node-version: 18
+          node-version: 20
       - run: npm ci
       - run: npx prettier .
 
@@ -77,7 +77,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3
         with:
-          node-version: 18
+          node-version: 20
       - run: npm ci
       - run: npx tsc
 
@@ -94,7 +94,7 @@ jobs:
     steps:
       - uses: actions/setup-node@v3
         with:
-          node-version: 18
+          node-version: 20
           registry-url: https://registry.npmjs.org
       - uses: actions/download-artifact@v3
         with: { name: package }