Add Laravel 7 support (#40)

Author: kapersoft

composer.json

@@ -14,13 +14,13 @@
     "require": {
         "php": ">=7.2",
         "guzzlehttp/guzzle": "^6.2",
-        "illuminate/notifications": "5.5.*|5.6.*|5.7.*|5.8.*|^6.0",
-        "illuminate/support": "5.5.*|5.6.*|5.7.*|5.8.*|^6.0"
+        "illuminate/notifications": "~5.5 || ^6.0 || ^7.0",
+        "illuminate/support": "~5.5 || ^6.0 || ^7.0"
     },
     "require-dev": {
         "mockery/mockery": "^1.0",
         "phpunit/phpunit": "~8.0",
-        "orchestra/testbench": "~3.5|~3.6|~3.7|~3.8",
+        "orchestra/testbench": "^4.0 || ^5.0",
         "dms/phpunit-arraysubset-asserts": ">=0.1.0"
     },
     "autoload": {