Add conflict for symfony/framework-bundle versions that break enum se…

…rializing (#6292)

Co-authored-by: Gwendolen Lynch <gwendolen.lynch@gmail.com>

composer.json

@@ -107,6 +107,7 @@
         "doctrine/orm": "<2.14.0",
         "doctrine/mongodb-odm": "<2.4",
         "doctrine/persistence": "<1.3",
+        "symfony/framework-bundle": "6.4.6 || 7.0.6",
         "symfony/var-exporter": "<6.1.1",
         "phpunit/phpunit": "<9.5",
         "phpspec/prophecy": "<1.15",