Remove trailing whitespace (#3668)

Foundation/include/Poco/EventChannel.h

@@ -30,7 +30,7 @@ namespace Poco {
 class Foundation_API EventChannel: public Channel
 	/// The EventChannel fires the messageLogged event for every log message
 	/// received. This can be used to hook custom log message processing into
-	/// the logging framework. 
+	/// the logging framework.
 {
 public:
 	using Ptr = AutoPtr<EventChannel>;