use NodeJS 18 as default in tests (#3745)

.github/workflows/crux-test.yml

@@ -14,7 +14,7 @@ jobs:
     - name: Use Node.js
       uses: actions/setup-node@v3
       with:
-        node-version: '16.x'
+        node-version: '18.x'
     - name: Install sitespeed.io
       run: npm ci
     - name: Run tests with CruX

.github/workflows/linux.yml

@@ -14,7 +14,7 @@ jobs:
     - name: Use Node.js
       uses: actions/setup-node@v3
       with:
-        node-version: '16.x'
+        node-version: '18.x'
     - name: Install sitespeed.io
       run: npm ci
     - name: Install Chrome

.github/workflows/safari.yml

@@ -14,7 +14,7 @@ jobs:
     - name: Use Node.js
       uses: actions/setup-node@v3
       with:
-        node-version: '16.x'
+        node-version: '18.x'
     - name: Install dependencies 
       run: |
         sudo safaridriver --enable 

.github/workflows/unittests.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [14.x, 16.x]
+        node-version: [14.x, 16.x, 18.x]
     steps:
     - uses: actions/checkout@v3
     - name: Use Node.js ${{ matrix.node-version }}

.github/workflows/windows.yml

@@ -14,7 +14,7 @@ jobs:
     - name: Use Node.js
       uses: actions/setup-node@v3
       with:
-        node-version: '16.x'
+        node-version: '18.x'
     - name: Install sitespeed.io
       run: npm ci
       env: