Update dependency phpunit/phpunit to ^9.6.22

Author: renovate[bot]

composer.json

@@ -35,7 +35,7 @@
 		"automattic/vipwpcs": "^3.0",
 		"dealerdirect/phpcodesniffer-composer-installer": "^1.0",
 		"johnpbloch/wordpress": "dev-master",
-		"phpunit/phpunit": "^9.6.13",
+		"phpunit/phpunit": "^9.6.22",
 		"wp-cli/wp-cli-bundle": "^2.8",
 		"wp-phpunit/wp-phpunit": "^6.4.2",
 		"xwp/wait-for": "^0.0.2",