ci: update Nightwatch workflow to fix wmic.exe issue

[GaneshPatil7517]

This pull request updates the GitHub Actions workflow (nightwatch-tests.yml)
to avoid using wmic.exe, which is deprecated on Windows 11.

• Ensures CI runs smoothly on Node.js 20+
• Prepares for multi-browser test support in Nightwatch

---

Summary by cubic

Updated the Nightwatch CI workflow to avoid the deprecated wmic.exe and run reliable cross-browser tests on Node 18 and 20. Also refreshed the README with a brief overview and setup notes.

• New Features
  • Added a test matrix: Node [18.x, 20.x] and browsers [chrome, firefox].
  • Installed Firefox conditionally and XVFB for headless runs.
  • Ran tests via xvfb-run with per-browser env: npm run ci-test -- --env ${{ matrix.browser }}.
  • Updated README with suite features and quick setup.

[cubic-dev-ai]

2 issues found across 2 files

Prompt for AI agents (all 2 issues)

Understand the root cause of the following 2 issues and fix them.


<file name="README.md">

<violation number="1" location="README.md:27">
Unclosed fenced code block in Setup section; add a closing ``` to fix Markdown rendering.</violation>
</file>

<file name=".github/workflows/nightwatch-tests.yml">

<violation number="1" location=".github/workflows/nightwatch-tests.yml:34">
Install apt packages non-interactively and update package lists to avoid CI hangs/failures.</violation>
</file>

---

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[cubic-dev-ai]

Unclosed fenced code block in Setup section; add a closing ``` to fix Markdown rendering.

Prompt for AI agents

Address the following comment on README.md at line 27:

<comment>Unclosed fenced code block in Setup section; add a closing ``` to fix Markdown rendering.</comment>

<file context>
@@ -13,3 +13,16 @@ Run tests
+
+## Setup
+1. Clone the repo:
+   ```bash
+   git clone https://github.com/dikwickley/element-v3-regression-test-suite.git
</file context>

[GaneshPatil7517]

name: Nightwatch Tests

on:
push:
branches: [ main ]
pull_request:
branches: [ main ]

jobs:
test:
runs-on: ubuntu-latest
strategy:
matrix:
node-version: [18.x, 20.x]
browser: [chrome, firefox]
steps:
- uses: actions/checkout@v3

  - name: Use Node.js ${{ matrix.node-version }}
    uses: actions/setup-node@v3
    with:
      node-version: ${{ matrix.node-version }}

  - name: Install dependencies
    run: npm install

  - name: Install Firefox
    run: sudo apt-get update && sudo apt-get install -y firefox

  - name: Install XVFB
    run: sudo apt-get update && sudo apt-get -y install xvfb

  - name: Run tests
    run: xvfb-run --auto-servernum npm run ci-test -- --env ${{ matrix.browser }}