Add writing-mode as a typography block support

[poena]

This ticket is for tracking the PHP backport for the following Gutenberg PR:
​https://github.com/WordPress/gutenberg/pull/50822

[poena]

Add writing-mode typography block support

Trac ticket: https://core.trac.wordpress.org/ticket/59306

Just doing a quick PR from the patch on the ticket to run CI on it (and also because I find the GH diff easier to read 😄)

[isabel_brison]

Changes LGTM; there was a linting error which I fixed in the attached PR: ​https://github.com/WordPress/wordpress-develop/pull/5210

I was wondering if we should add a test for this feature in the typography test suite: ​https://github.com/WordPress/wordpress-develop/blob/trunk/tests/phpunit/tests/block-supports/typography.php but we're not being consistent with tests for other discreet features such as letter-spacing or text-decoration so I guess we could leave this as is and revisit those tests later as a whole.

[isabel_brison]

In 56605:

Editor: add text orientation for blocks with typography support.

Adds a new text orientation option to the typography block support, implemented with CSS writing-mode.

Props poena.
Fixes #59306.

committed in r56605.

[andrewserong]

In 59199:

Editor: Fix writingMode support in dynamic blocks.

Adds missing handling for the typography.writingMode property to the style engine, so that dynamic blocks correctly render text orientation styles on the site frontend.

Props wildworks, aaronrobertshaw, poena, get_dave, ndiego.
Fixes #62189.
See #59306.