Update league/flysystem requirement from ^2.2 to ^3.18

Updates the requirements on [league/flysystem](https://github.com/thephpleague/flysystem) to permit the latest version.
- [Release notes](https://github.com/thephpleague/flysystem/releases)
- [Changelog](https://github.com/thephpleague/flysystem/blob/3.x/CHANGELOG.md)
- [Commits](thephpleague/flysystem@2.2.0...3.18.0)

---
updated-dependencies:
- dependency-name: league/flysystem
  dependency-type: direct:production
...

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

composer.json

@@ -29,7 +29,7 @@
     "cleverage/process-bundle": "^3.2",
     "easycorp/easyadmin-bundle": "^4.0",
     "ddtraceweb/monolog-parser": "^1.3",
-    "league/flysystem": "^2.2",
+    "league/flysystem": "^3.18",
     "composer/package-versions-deprecated": "^1.11",
     "doctrine/doctrine-bundle": "^2.4",
     "doctrine/doctrine-migrations-bundle": "^3.1",