Fixed error versions for hyperf/engine. (#7429)

Author: limingxinleo

composer.json

@@ -18,7 +18,7 @@
         "hyperf/coordinator": "~3.1.0",
         "hyperf/coroutine": "~3.1.0",
         "hyperf/di": "~3.1.0",
-        "hyperf/engine": "~3.1.0",
+        "hyperf/engine": "^2.0",
         "hyperf/redis": "~3.1.0",
         "hyperf/websocket-server": "~3.1.0",
         "psr/container": "^1.0 || ^2.0"