Update composer.json

Add support for Laravel 6.3

Author: dannyvankooten

composer.json

@@ -12,8 +12,8 @@
   "require": {
     "php": ">=7.1",
     "ibericode/vat": "^1.2",
-    "illuminate/contracts": "5.5.*|5.6.*|5.7.*|5.8.*|6.0.*|6.2.*",
-    "illuminate/support": "5.5.*|5.6.*|5.7.*|5.8.*|6.0.*|6.2.*"
+    "illuminate/contracts": "5.5.*|5.6.*|5.7.*|5.8.*|6.0.*|6.2.*|6.3.*",
+    "illuminate/support": "5.5.*|5.6.*|5.7.*|5.8.*|6.0.*|6.2.*|6.3.*"
   },
   "require-dev": {
     "phpunit/phpunit": "^6.3|^7.0",