Add support for php-mqtt/client:^2.0 (#48)

Author: Namoshek

composer.json

@@ -22,7 +22,7 @@
         "php": "^7.4|^8.0",
         "illuminate/config": "^7.0|^8.0|^9.0|^10.0",
         "illuminate/support": "^7.0|^8.0|^9.0|^10.0",
-        "php-mqtt/client": "^1.3.0"
+        "php-mqtt/client": "^1.3.0|^2.0"
     },
     "require-dev": {
         "squizlabs/php_codesniffer": "^3.5"