[WIP] Global styles: add text alignment section

[sejas]

WORK IN PROGRESS. For now, it's just a dummy UI with no real interaction.

• Closes Global Styles: Add alignment support in global typography styles #48202

What?

It adds text-alignment option to global styles.

Why?

Before adding justified text alignment at the block level, we will add the text alignment as a global style.
In this PR I suggest adding a text-alignment section to edit the text-alignment itself and hyphens on the global style.

How?

We are adding a new section to GlobalStylesUI.

Testing Instructions

• On /wp-admin/ go to Appearance>Editor`
• Click on Styles
• Click on the pencil icon to edit styles
• Observe the new section Text alignment is present below Typography
• Click on it Text alignment
• Observe the options Alignment and Hyphens are present. For now these options do nothing. It's still work in progress.

Testing Instructions for Keyboard

Screenshots or screencast

Screencast

global-text-alignment.mp4

Playground PR LIve preview

https://playground.wordpress.net/?gutenberg-pr=52426&url=/wp-admin/site-editor.php

[github-actions]

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