Update composer.json

Author: GrahamCampbell

composer.json

@@ -13,12 +13,12 @@
         "php": "^7.0",
         "illuminate/contracts": "5.1.*|5.2.*|5.3.*|5.4.*|5.5.*",
         "illuminate/support": "5.1.*|5.2.*|5.3.*|5.4.*|5.5.*",
-        "league/commonmark": "^0.15|^0.16"
+        "league/commonmark": "^0.17"
     },
     "require-dev": {
         "graham-campbell/analyzer": "^2.0",
-        "graham-campbell/markdown": "^8.0",
-        "graham-campbell/testbench": "^4.0",
+        "graham-campbell/markdown": "^9.0",
+        "graham-campbell/testbench": "^4.0|^5.0",
         "phpunit/phpunit": "^6.5"
     },
     "autoload": {
@@ -36,7 +36,7 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "2.1-dev"
+            "dev-master": "2.2-dev"
         },
         "laravel": {
             "providers": [