misc: update copyright date

AudioFilter/FilterAudioSubscriber.cpp

AudioFilter/FilterAudioSubscriber.h

AudioFilter/FilterMediaHandler.cpp

AudioFilter/FilterMediaHandler.h

AudioFilter/main.cpp

AutoAnswer/BotChatHandler.cpp

AutoAnswer/BotChatHandler.h

AutoAnswer/BotPeerChatSubscriber.cpp

AutoAnswer/BotPeerChatSubscriber.h

AutoAnswer/main.cpp

GreenScreen/main.cpp

GreenScreen/pluginMediaHandler.cpp

GreenScreen/pluginMediaHandler.h

GreenScreen/pluginProcessor.cpp

GreenScreen/pluginProcessor.h

GreenScreen/videoSubscriber.cpp

GreenScreen/videoSubscriber.h

HelloWorld/CenterCircleMediaHandler.cpp

HelloWorld/CenterCircleMediaHandler.h

HelloWorld/CenterCircleVideoSubscriber.cpp