PB-480: [Docs] Update content type styling concepts

fixed base_form reference

Co-Authored-By: Anthoula Wojczak <anthoula@users.noreply.github.com>

Author: bdenham

docs/how-to/how-to-configure-styling-options.md

@@ -10,7 +10,7 @@ Before we dive into the particulars of using different configuration options, le
 
 ![Understanding the big picture](../images/styling-big-picture.svg)
 
-1. **Heading Form** (`pagebuilder_heading_form.xml`). This form inherits from the `pagebuilder_base_form.xml`, which provides most of the input fields for the Heading. The Heading form itself provides input fields selecting an `appearance`, entering the `heading_text`, and selecting a `heading_type` (`h1` to `h6`). The text to the left of each field specifies which form the field comes from, the `heading_form` or the `base form`.
+1. **Heading Form** (`pagebuilder_heading_form.xml`). This form inherits from the `pagebuilder_base_form.xml`, which provides most of the input fields for the Heading. The Heading form itself provides input fields selecting an `appearance`, entering the `heading_text`, and selecting a `heading_type` (`h1` to `h6`). The text to the left of each field specifies which form the field comes from, the `heading_form` or the `base_form`.
 
 2. **Heading Configuration** (`heading.xml`). The main purpose of all content type configuration files is to provide the data mapping between the form fields and the HTML templates. Configurations map to fields with matching names.