Upgrade dependencies to support Laravel 8

Author: miracuthbert

composer.json

@@ -15,15 +15,16 @@
         }
     ],
     "require": {
-        "php": "^7.1.3",
-        "illuminate/console": "^6.0|^7.0",
-        "illuminate/database": "^6.0|^7.0",
-        "illuminate/http": "^6.0|^7.0",
-        "illuminate/support": "^6.0|^7.0"
+        "php": ">=7.3.0",
+        "illuminate/console": ">=6.0",
+        "illuminate/database": ">=6.0",
+        "illuminate/http": ">=6.0",
+        "illuminate/support": ">=6.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^8.0",
-        "orchestra/testbench": "^3.8"
+        "phpunit/phpunit": "^8.2.4",
+        "orchestra/testbench": "^6.2",
+        "laravel/legacy-factories": "1.0.4"
     },
     "autoload": {
         "psr-4": {