Specify node versions a la sass/sass-spec#1957

.github/workflows/ci.yml

@@ -5,7 +5,6 @@ defaults:
 
 env:
   PROTOC_VERSION: 3.x
-  DEFAULT_NODE_VERSION: 20.x # If changing this, also change jobs.tests.strategy.matrix.node_version
 
 on:
   push:
@@ -22,7 +21,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v2
         with:
-          node-version: ${{ env.DEFAULT_NODE_VERSION }}
+          node-version: 'lts/*'
           check-latest: true
 
       - name: Check out the language repo
@@ -43,7 +42,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu, macos, windows]
-        node-version: [20.x, 18.x, 16.x] # If changing this, also change env.DEFAULT_NODE_VERSION
+        node-version: ['lts/*', 'lts/-1', 'lts/-2']
       fail-fast: false
 
     steps:
@@ -73,9 +72,6 @@ jobs:
       - run: npm run compile
       - run: node test/after-compile-test.mjs
 
-  # The versions should be kept up-to-date with the latest LTS Node releases.
-  # They next need to be rotated October 2021. See
-  # https://github.com/nodejs/Release.
   sass_spec:
     name: 'JS API Tests | Node ${{ matrix.node_version }} | ${{ matrix.os }}'
     runs-on: ${{ matrix.os }}-latest
@@ -84,13 +80,13 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu, windows, macos]
-        node_version: [20]
+        node_version: ['lts/*']
         include:
           # Include LTS versions on Ubuntu
           - os: ubuntu
-            node_version: 18
+            node_version: lts/-1
           - os: ubuntu
-            node_version: 16
+            node_version: lts/-2
 
     steps:
       - uses: actions/checkout@v2
@@ -147,7 +143,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v2
         with:
-          node-version: ${{ env.DEFAULT_NODE_VERSION }}
+          node-version: 'lts/*'
           check-latest: true
           registry-url: 'https://registry.npmjs.org'
       - run: npm install