Try again to use it with symfony 4

Author: Christoph Singer

Tests/Fixtures/app/config/config.yml

@@ -3,6 +3,7 @@ framework:
 services:
     wa72_jsonrpc.testservice:
         class: 'Wa72\JsonRpcBundle\Tests\Testservice'
+        public: true
         tags:
           - {name: wa72_jsonrpc.exposable}
     # override jms_serializer.form_error_handler with dummy

composer.json

@@ -14,7 +14,7 @@
     ],
     "require":{
         "php":">=5.4",
-        "symfony/symfony":"~2.7|~3.0",
+        "symfony/symfony":"^2.7|^3|^4",
         "jms/serializer-bundle":"^1.1|^2"
     },
     "require-dev": {