fix/35860: Adds missing aria-label and tabindex HTML attributes to the Help tip element.

[Sidsector9]

Submission Review Guidelines:

• I have followed the WooCommerce Contributing Guidelines and the WordPress Coding Standards.
• I have checked to ensure there aren't other open Pull Requests for the same update/change.
• I have reviewed my code for security best practices.
• Following the above guidelines will result in quick merges and clear and detailed feedback when appropriate.

Changes proposed in this Pull Request:

Adds missing aria-label and tabindex HTML attributes to the Help tip element.

Closes #35860

How to test the changes in this Pull Request:

Using the WooCommerce Testing Instructions Guide, include your detailed testing instructions:

1. Go to Products > Add New (/wp-admin/post-new.php?post_type=product)
2. Search for the class .woocommerce-help-tip on the product edit page using Inspector tool on the trunk branch.
3. Observe that some matched elements don't have aria-label and tabindex attribute set.
4. Switch to the fix branch and repeat step (1)
5. Observe matched elements have missing attributes from step (2)
6. Enable screen reader such as VoiceOver
7. Confirm you can navigate to help tip elements using the keyboard and the screen reader can read the text.

[chihsuan]

Thanks for the fix! 👍

Except for the one in the comment, I confirmed the others are visible to screen readers now.

[chihsuan]

LGTM and tested well!

I'll wait for @coreymckrill to take a look and merge it.

[codecov]

Codecov Report

Merging #37808 (410490e) into trunk (e8fcfbb) will decrease coverage by 0.0%.
The diff coverage is 100.0%.

Additional details and impacted files

@@            Coverage Diff             @@
##             trunk   #37808     +/-   ##
==========================================
- Coverage     51.5%    51.5%   -0.0%     
- Complexity   17261    17280     +19     
==========================================
  Files          429      430      +1     
  Lines        79957    80026     +69     
==========================================
  Hits         41215    41215             
- Misses       38742    38811     +69     

Impacted Files	Coverage Δ
plugins/woocommerce/includes/wc-core-functions.php	63.6% <100.0%> (ø)

... and 3 files with indirect coverage changes

[coreymckrill]

Nice work @Sidsector9!