Update jetpack extension tests to work with update to @WordPress depe…

…ndencies (#20326)

* Update jetpack extension tests to work with updates @WordPress dependencies
* Add babel nullish-coalescing-operator plugin
* Provide `isRTL` as an export in the `i18n-to-php.js` webpack extension
* Add missing style that has been removed from latest @wordpress/components
* Add JSDOM to mock document for emotion library
* Exclude extensions/shared/i18n-to-php from its own webpack module remapping so some methods from real package can be imported and re-exported
* Fix mapping to dependency-extraction-webpack-plugin util file
* Mock CSS global in StaticSiteGeneratorPlugin config
* Update react to match what @wordpress/* wants otherwise we get hundreds of "Invalid hook call" errors.
* Update "validate-es5" to "validate-es9" Babel does less transpilation now that @wordpress/browserslist-config
dropped IE11. ES9 is the minimum version that passes now. Longer term we should replace that check with something better. See p9dueE-3fG-p2 for details.
* Update Jetpack change entry

Co-authored-by: Glen Davies <glen.davies@a8c.com>
Co-authored-by: Marcelo Serpa <81248+fullofcaffeine@users.noreply.github.com>
Co-authored-by: Brad Jorsch <brad.jorsch@automattic.com>

package.json

@@ -93,6 +93,7 @@
 	},
 	"pnpm": {
 		"overrides": {
+			"@automattic/calypso-build>enzyme-adapter-react-16@*": "npm:@wojtekmaj/enzyme-adapter-react-17@0.6.3",
 			"@automattic/calypso-build>node-sass@4.13.0": "^4.13.0",
 			"yargs@^7.1.0>yargs-parser": "^20.0.0",
 			"isomorphic-fetch@^2.1.1>node-fetch": "^2.6.1",