Block Library: Migrate to the new textAlign block support

[t-hamano]

What problem does this address?

Over 20 core blocks have attributes and UI implemented for each block to control the text-align style. For example, it looks like the following.

block.json

{
	"$schema": "https://schemas.wp.org/trunk/block.json",
	"apiVersion": 3,
	"name": "core/heading",
	"title": "Heading",
	"attributes": {
		"textAlign": {
			"type": "string"
		}
	}
}

edit.js

import {
	AlignmentControl,
	BlockControls,
	useBlockProps,
} from '@wordpress/block-editor';

function Edit( { attributes, setAttributes } ) {
	const { textAlign } = attributes;
	return (
		<>
			<BlockControls group="block">
				<AlignmentControl
					value={ textAlign }
					onChange={ ( nextAlign ) => {
						setAttributes( { textAlign: nextAlign } );
					} }
				/>
			</BlockControls>
			<div { ...useBlockProps() } />
		</>
	);
}

These are all almost the same implementations and feel redundant.

What is your proposed solution?

In #59531, textAlign is added as block support. I believe that we can gradually migrate to this block support.

Below is a list of blocks that provide attributes and UI to control text-aligin.

• core/button
• core/comment-author-name
• core/comment-content
• core/comment-edit-link
• core/comment-reply-link
• core/comment-title
• core/heading
• core/paragraph: Note that the attribute is named "align" and not "textAlign".
• core/post-author: This might not be necessary as Deprecate 'Post author' block #55352 is considering deprecating this block.
• core/post-author-biography
• core/post-author-name
• core/post-comments-count
• core/post-comments-form
• core/post-comments-link
• core/post-date
• core/post-excerpt
• core/post-navigation-link
• core/post-terms
• core/post-time-to-read
• core/post-title
• core/pullquote
• core/query-title
• core/site-tagline
• core/site-title
• core/term-description
• core/verse