Add About page and update navigation to include GHAS information

[CalinL]

No description provided.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Snapshot Warnings

⚠️: No snapshots were found for the head SHA e7cd762.

Ensure that dependencies are being submitted on PR branches and consider enabling retry-on-snapshot-warnings. See the documentation for more information and troubleshooting advice.

Scanned Files

None

[Copilot]

Pull Request Overview

This PR adds a dedicated About page describing GitHub Advanced Security and updates the site navigation to incorporate links to this page.

• Added a new About page (both view and page model)
• Updated the shared layout and Index page to include navigation links to the About page

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
src/webapp01/Pages/Shared/_Layout.cshtml	Added a navigation link to the About page
src/webapp01/Pages/Index.cshtml	Included an About page link in the main content area
src/webapp01/Pages/About.cshtml.cs	Added a new PageModel for the About page
src/webapp01/Pages/About.cshtml	Created the About page with GHAS details

Comments suppressed due to low confidence (2)

src/webapp01/Pages/Shared/_Layout.cshtml:27

• [nitpick] Consider aligning the link text with the page title ('About GitHub Advanced Security') for consistency.

<a class="nav-link text-dark" asp-area="" asp-page="/About">About GHAS</a>

src/webapp01/Pages/Index.cshtml:11

• [nitpick] Ensure consistency between the navigation label 'About GHAS' and the page title 'About GitHub Advanced Security' to avoid user confusion.

<p class="card-text">Visit our <a asp-page="/About">About GHAS</a> page to learn about GitHub Advanced Security features.</p>