Direct/Freedom outbound: Better Compatibility (#6058)

Fixes https://github.com/XTLS/Xray-core/issues/6393

common/session/session.go

@@ -70,8 +70,6 @@ type Outbound struct {
 	Tag string
 	// Name of the outbound proxy that handles the connection.
 	Name string
-	// Unused. Conn is actually internet.Connection. May be nil. It is currently nil for outbound with proxySettings
-	Conn net.Conn
 	// CanSpliceCopy is a property for this connection
 	// 1 = can, 2 = after processing protocol info should be able to, 3 = cannot
 	CanSpliceCopy int