Allow 0.8 version of queue interop

Author: makasim

composer.json

@@ -5,7 +5,7 @@
   "minimum-stability": "stable",
   "require": {
     "php": "^7.1.3",
-    "queue-interop/queue-interop": "^0.7"
+    "queue-interop/queue-interop": "^0.7|^0.8"
   },
   "require-dev": {
     "phpunit/phpunit": "~5.4.0"