Updating version requirement for the main framework

Author: jeremeamia

composer.json

@@ -17,7 +17,7 @@
     },
     "require": {
         "amphp/websocket-client": "^1.0",
-        "slack-php/slack-app-framework": "^0.4.0"
+        "slack-php/slack-app-framework": ">=0.5.0"
     },
     "autoload": {
         "psr-4": {