Update laravel/framework requirement from 5.7.* || 5.8.* || 6.0.*… (#8)

Update laravel/framework requirement from 5.7.* || 5.8.* || 6.0.* to 5.7.* || 5.8.* || 6.0.* || 6.1.*

Author: Kevin Buchholz

composer.json

@@ -26,7 +26,7 @@
     "require": {
         "php": ">=7.1",
         "eloquent/enumeration": "^6.0",
-        "laravel/framework": "5.7.* || 5.8.* || 6.0.*"
+        "laravel/framework": "5.7.* || 5.8.* || ^6.0"
     },
     "require-dev": {
         "consistence/coding-standard": "3.7",