Removed support for illuminate/support ^6.0

L7 uses the Throwable interface where's Laravel 6 still uses the Exception class.

Author: naillizard

composer.json

@@ -12,7 +12,7 @@
     ],
     "require": {
         "php": "^7.2",
-        "illuminate/support": "^6.0|^7.0"
+        "illuminate/support": "^7.0"
     },
     "require-dev": {
         "orchestra/testbench": "^4.0",