ci: set COMPOSER_ROOT_VERSION to 4.4.x-dev

The 4.4 maintenance branch inherited a stale 4.3.x-dev value from
main. Each release branch pins its own dev version (cf. 4.3, 4.2).

Author: soyuka

.github/workflows/ci.yml

@@ -21,7 +21,7 @@ concurrency:
 
 env:
   COMPOSER_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-  COMPOSER_ROOT_VERSION: "4.3.x-dev"
+  COMPOSER_ROOT_VERSION: "4.4.x-dev"
 
 jobs:
   architecture: