Closes #485 Remove unused CSS files in az_flexible_page module

[BaoNguyen09]

Description

I deleted 2 css files: az_flexible_page.css and az_flexible_page_layout.css in az_flexible_page module

Related issues

Closes #485

How to test

Types of changes

Arizona Quickstart (install profile, custom modules, custom theme)

• Patch release changes
  • Bug fix
  • Accessibility, performance, or security improvement
  • Critical institutional link or brand change
  • Adding experimental module
  • Update experimental module
• Minor release changes
  • New feature
  • Breaking or visual change to existing behavior
  • Upgrade experimental module to stable
  • Enable existing module by default or database update
  • Non-critical brand change
  • New internal API or API improvement with backwards compatibility
  • Risky or disruptive cleanup to comply with coding standards
  • High-risk or disruptive change (requires upgrade path, risks regression, etc.)
• Other or unknown
  • Other or unknown

Drupal core

• Patch release changes
  • Security update
  • Patch level release (non-security bug-fix release)
  • Patch removal that's no longer necessary
• Minor release changes
  • Major or minor level update
• Other or unknown
  • Other or unknown

Drupal contrib projects

• Patch release changes
  • Security update
  • Patch or minor level update
  • Add new module
  • Patch removal that's no longer necessary
• Minor release changes
  • Major level update
• Other or unknown
  • Other or unknown

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.
• My change requires release notes.

[bberndt-uaz]

I believe these files are safe to delete. Here is the history of these two CSS files and AZ Flexible Page libraries:

1. az_flexible_page.css and az_flexible_page_layout.css were added to the module and defined as assets in az_flexible_page.libraries:

   • Fixes #40 Implement LayoutBuilder subclass #42

2. The original az_flexible_page.libraries was deleted and the CSS files were left in the module folder:

   • Fixes #280, fixes #277 Remove Layout Builder Customizations #281

3. az-flexible-page-edit-form.css was added and defined as an asset in a new libraries file:

   • Fix spacing issue on Page content type #484

4. az_flexible_page.theme.css was added and defined as a second asset in the libraries file:

   • Closes #916 — Restore the Barrio node__content margin-top, override it on az_flexible_page. #921

[joshuasosa]

As far as I could see, I don't think these CSS files currently in use. Should be ok to clean up!