Update required php version from 7.2 to 7.4

Author: benycode

composer.json

@@ -15,7 +15,7 @@
     ],
     "minimum-stability": "stable",
     "require": {
-        "php": "^7.2",
+        "php": "^7.4",
         "ext-json": "*",
         "illuminate/contracts": ">=5.5",
         "illuminate/support": ">=5.5"