Accessibility: Bump headings for BuddyPress forums

[mercime]

Continuing with BP's accessibility improvements, I will be uploading a patch to bump the headings for the group forums and some before and after screenshots for your kind consideration. Thank you.

[espellcaste]

@mercime I think I'm lost here... I always thought and learned that h1, h2 h3 was the proper way instead of h1, h2, h2...

Am I wrong or just uniformed? :/

[mercime]

@espellcaste Thank you for your question. h1, h2, h3, ... is the heading hierarchy while what we are addressing here is the HTML document outline that organizes specific content/section with the other content of a webpage.

For example in the first image above GroupForum.png, you'll find the following structure in the "Before" screenshot:

h1 - bbPress Testing
-- h2 - Group Admin
----- h3 - Group Forum

The above structure doesn't make sense as the Group Forum content is directly relevant to h1 bbPress Testing as a whole and not related to h2 Group Admin list specifically.

The proposed change below aligns the Group Forum content to the structure it is meant to show in the first place: it's a section that provides supplementary information for h1 bbPress Testing and not the h2 Group Admin list.

h1 - bbPress Testing
-- h2 - Group Admin
-- h2 - Group Forum

[espellcaste]

@mercime Now I get what you are trying to do. Thanks for the feedack.

[netweb]

In 6202:

Accessibility: Bump headings for BuddyPress group forums.

Props mercime.
Fixes #2968.