Update headings font selector: drop tp-caption, add Bootstrap 5 classes

[jjroelofs]

Summary

The headings_font_face_selector default value includes .html .tp-caption (Revolution Slider), which has not been used for a long time. It should be removed and replaced with modern Bootstrap 5 heading classes.

What is the current bug behavior?

Default selector: h1,h2,h3,h4,h5,h6,label,.field--label,.page-title, .html .tp-caption

• Includes obsolete .tp-caption selector
• Missing Bootstrap 5 heading classes .h1–.h6 and .display-1–.display-6

What is the expected correct behavior?

Default selector: h1,.h1,h2,.h2,h3,.h3,h4,.h4,h5,.h5,h6,.h6,.display-1,.display-2,.display-3,.display-4,.display-5,.display-6,label,.field--label,.page-title

Scope of affected files

• config/install/dxpr_theme.settings.yml
• features/sooper-fonts/fonts-theme-settings.inc
• dxpr_theme_STARTERKIT/config/install/dxpr_theme_STARTERKIT.settings.yml