Update workflows to use Node.js 22.14.0 (#1116)

## Description

### Why
GitHub Actions workflow templates were using default runner Node.js
versions, which may vary across runner images and become outdated.
Pinning to Node.js 22.14.0 ensures consistent build environments across
all CI runs.

### Changes
- Added `actions/setup-node@v4` to `template-upgradesample.yml` and
`template-buildsample.yml`
- Node.js 22.14.0 is now configured immediately after checkout in both
workflow templates
- Affects all workflows that call these templates: `ci.yml`, `pr.yml`,
and `ci-upgrade.yml`

## Screenshots
N/A - Workflow configuration changes only

<!-- START COPILOT ORIGINAL PROMPT -->



<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>Update workflows to use node version >=
22.14.0</issue_title>
> <issue_description>Make changes in this file alone
template-upgradesample.yml, template-buildsample.yml</issue_description>
> 
> <agent_instructions>Create a PR so that all workflow will use node
version 22.14.0 for wherever it is necessary.</agent_instructions>
> 
> ## Comments on the Issue (you are @copilot in this section)
> 
> <comments>
> </comments>
> 


</details>



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- Fixes #1115

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---

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###### Microsoft Reviewers: [Open in
CodeFlow](https://microsoft.github.io/open-pr/?codeflow=https://github.com/microsoft/react-native-windows-samples/pull/1116)

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: vineethkuttan <66076509+vineethkuttan@users.noreply.github.com>

Author: Copilot

.github/workflows/template-buildsample.yml

@@ -54,6 +54,11 @@ jobs:
     steps:
     - uses: actions/checkout@v3
 
+    - name: Setup Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: '22.14.0'
+
     - name: Gather environment info
       run: npx envinfo
 

.github/workflows/template-upgradesample.yml

@@ -65,6 +65,11 @@ jobs:
     steps:
     - uses: actions/checkout@v3
 
+    - name: Setup Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: '22.14.0'
+
     - name: Gather environment info
       run: npx envinfo