[v25-branch]: Update johnpbloch/wordpress requirement

Updates the requirements on [johnpbloch/wordpress](https://github.com/johnpbloch/wordpress) to permit the latest version.
- [Commits](johnpbloch/wordpress@6.8.3...6.8.4)

---
updated-dependencies:
- dependency-name: johnpbloch/wordpress
  dependency-version: 6.8.4
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

composer.json

@@ -11,7 +11,7 @@
   "require": {
     "php": ">=8.2",
     "stuttter/wp-user-signups": "^5.0.2",
-    "johnpbloch/wordpress": "6.8.3",
+    "johnpbloch/wordpress": "6.8.4",
     "altis/cms-installer": "^0.4.4",
     "humanmade/clean-html": "^2.0.0",
     "humanmade/altis-reusable-blocks": "~0.2.4",