Allow v3 contracts where possible

Author: derrabus

composer.json

@@ -17,7 +17,7 @@
     ],
     "require": {
         "php": ">=7.2.5",
-        "symfony/deprecation-contracts": "^2.1"
+        "symfony/deprecation-contracts": "^2.1|^3"
     },
     "require-dev": {
         "symfony/console": "^4.4|^5.0|^6.0",