Docs: Fix a few minor issues in Create block theme documentation page

[audrasjb]

Description

This PR aims to fix a few minor issues in the Create block theme documentation page:

• replace backticks with <code> in callouts since backticks are not interpreted when using inside HTML bits
• remove some unwanted line breaks
• fix some missing list declarations
• fix an issue in the name of a parameter

How has this been tested?

N/A.

Screenshots

N/A.

Types of changes

Bug fix (non-breaking change which fixes an issue)

[carolinan]

I think this update needs to wait until we know for sure how the templates and template parts will be accessed.

For example it still says:

There are several ways to create templates and template parts:

Manually, by creating HTML files containing block markup.
Using the site editor.
Using the template editing mode in the block editor.
The fourth way is temporary and involves going to the Appearance menu > Templates, and is not recommended because of its limitations.

https://developer.wordpress.org/block-editor/how-to-guides/themes/create-block-theme/#creating-the-templates-and-template-parts

This was accurate at the time but is likely to change in the next days or hours. :)

[audrasjb]

Oh yes, got it. Then let's wait a few days before fixing the rest of the items :)

[carolinan]

Closing in favor of #37655 that has been updated to include some of the fixes from this PR.