[6.4] Allow 7.0 deps

Author: nicolas-grekas

composer.json

@@ -22,8 +22,8 @@
     "require-dev": {
         "symfony/event-dispatcher-contracts": "^2.5|^3",
         "symfony/http-client-contracts": "^2.5|^3",
-        "symfony/http-foundation": "^5.4|^6.0",
-        "symfony/messenger": "^5.4|^6.0"
+        "symfony/http-foundation": "^5.4|^6.0|^7.0",
+        "symfony/messenger": "^5.4|^6.0|^7.0"
     },
     "conflict": {
         "symfony/event-dispatcher": "<5.4",