docs: update nodejs template guide to match node versions

content/actions/guides/building-and-testing-nodejs.md

@@ -37,7 +37,11 @@ To get started quickly, add the template to the `.github/workflows` directory of
 ```yaml{:copy}
 name: Node.js CI
 
-on: [push]
+on:
+  push:
+    branches: [ $default-branch ]
+  pull_request:
+    branches: [ $default-branch ]
 
 jobs:
   build:
@@ -46,19 +50,17 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [8.x, 10.x, 12.x]
+        node-version: [10.x, 12.x, 14.x, 15.x]
 
     steps:
     - uses: actions/checkout@v2
     - name: Use Node.js ${{ matrix.node-version }}
       uses: actions/setup-node@v1
       with:
         node-version: ${{ matrix.node-version }}
-    - run: npm install
+    - run: npm ci
     - run: npm run build --if-present
     - run: npm test
-      env:
-        CI: true
 ```
 {% endraw %}
 
@@ -70,15 +72,15 @@ The easiest way to specify a Node.js version is by using the `setup-node` action
 
 The `setup-node` action takes a Node.js version as an input and configures that version on the runner. The `setup-node` action finds a specific version of Node.js from the tools cache on each runner and adds the necessary binaries to `PATH`, which persists for the rest of the job. Using the `setup-node` action is the recommended way of using Node.js with {% data variables.product.prodname_actions %} because it ensures consistent behavior across different runners and different versions of Node.js. If you are using a self-hosted runner, you must install Node.js and add it to `PATH`.
 
-The template includes a matrix strategy that builds and tests your code with three Node.js versions: 8.x, 10.x, and 12.x. The 'x' is a wildcard character that matches the latest minor and patch release available for a version. Each version of Node.js specified in the `node-version` array creates a job that runs the same steps.
+The template includes a matrix strategy that builds and tests your code with four Node.js versions: 10.x, 12.x, 14.x, and 15.x. The 'x' is a wildcard character that matches the latest minor and patch release available for a version. Each version of Node.js specified in the `node-version` array creates a job that runs the same steps.
 
 Each job can access the value defined in the matrix `node-version` array using the `matrix` context. The `setup-node` action uses the context as the `node-version` input. The `setup-node` action configures each job with a different Node.js version before building and testing code. For more information about matrix strategies and contexts, see "[Workflow syntax for {% data variables.product.prodname_actions %}](/actions/automating-your-workflow-with-github-actions/workflow-syntax-for-github-actions#jobsjob_idstrategymatrix)" and "[Context and expression syntax for {% data variables.product.prodname_actions %}](/actions/reference/context-and-expression-syntax-for-github-actions)."
 
 {% raw %}
 ```yaml
 strategy:
   matrix:
-    node-version: [8.x, 10.x, 12.x]
+    node-version: [10.x, 12.x, 14.x, 15.x]
 
 steps:
 - uses: actions/checkout@v2
@@ -116,11 +118,9 @@ jobs:
       uses: actions/setup-node@v1
       with:
         node-version: '12.x'
-    - run: npm install
+    - run: npm ci
     - run: npm run build --if-present
     - run: npm test
-      env:
-        CI: true
 ```
 {% endraw %}