Remove no longer needed `varbase_carousels_requirements()` function

Problem/Motivation

The varbase_carousels_requirements() function in
modules/contrib/varbase_carousels/includes/helpers.inc is no longer needed.
It was originally used for adding requirements to the Drupal Status Report page, but its logic is outdated and relies on deprecated drupal_get_path() calls.

Keeping this function causes unnecessary code maintenance and leads to errors in newer Drupal core versions (e.g., Drupal 10 and 11).

Proposed resolution

• Remove the varbase_carousels_requirements() function from includes/helpers.inc.
• Remove any related hook_requirements() invocations from the module.

Switch to use Bootstrap 5 Carousels

Remaining tasks

• ✅ File an issue about this project
• ✅ Addition/Change/Update/Fix to this project
• ✅ Testing to ensure no regression
• ➖ Automated unit/functional testing coverage
• ➖ Developer Documentation support on feature change/addition
• ➖ User Guide Documentation support on feature change/addition
• ➖ UX/UI designer responsibilities
• ➖ Accessibility and Readability
• ✅ Code review from 1 Varbase core team member
• ✅ Full testing and approval
• ✅ Credit contributors
• ✅ Review with the product owner
• ✅ Update Release Notes and Update Helper on new feature change/addition
• ✅ Release varbase-10.1.0-alpha3, varbase_carousels-10.1.0-alpha4, varbase-10.0.7, varbase_carousels-10.0.3, varbase-9.1.11 , varbase_carousels-9.1.7

Varbase update type

• ✅ No Update
• ➖ Optional Update
• ➖ Forced Update
• ➖ Forced Update if Unchanged

User interface changes

• N/A

API changes

• N/A

Data model changes

• N/A

Release notes snippet

• Issue #3541376: Removed no longer needed `varbase_carousels_requirements()` function