Remove dotnet5.4 from the remoting project as remoting is not supported in anything other than desktop .net

Rx.NET/Source/System.Reactive.Runtime.Remoting/project.json

@@ -40,39 +40,7 @@
               "HAS_WINFORMS",
               "USE_TIMER_SELF_ROOT"
             ]
-          },
-          "dependencies": {
-            "System.Reflection": "4.1.0-beta-23516"
-          }
-        },
-        "dotnet5.4": {
-            "compilationOptions": {
-              "define": [
-                "NO_EVENTARGS_CONSTRAINT",
-                "HAS_EDI",
-                "HAS_WINRT",
-                "HAS_PROGRESS",
-                "PREFER_ASYNC",
-                "HAS_AWAIT",
-                "HAS_APTCA",
-                "NO_REMOTING",
-                "NO_SERIALIZABLE",
-                "NO_THREAD",
-                "CRIPPLED_REFLECTION",
-                "PLIB",
-                "USE_TIMER_SELF_ROOT"
-              ]
-            },
-          "dependencies": {
-            "System.Collections.Concurrent": "4.0.11-beta-23516",
-            "System.ComponentModel": "4.0.1-beta-23516",
-            "System.Linq": "4.0.1-beta-23516",
-            "System.Linq.Queryable": "4.0.1-beta-23516",
-            "System.Threading": "4.0.11-beta-23516",
-            "System.Threading.Thread": "4.0.0-beta-23516",
-            "System.Threading.ThreadPool": "4.0.10-beta-23516",
-            "System.Threading.Timer": "4.0.1-beta-23516"
-          }
+          }    
         }
     }
 }