[PinObserver] Updated implementation following the new ButtonHandler

cmake/boardcore.cmake

src/shared/utils/ButtonHandler/ButtonHandler.cpp

src/shared/utils/ButtonHandler/ButtonHandler.h

src/shared/utils/GpioPinCompare.h

src/shared/utils/PinObserver.h

src/shared/utils/PinObserver/PinObserver.cpp

src/shared/utils/PinObserver/PinObserver.h

src/tests/test-pinobserver.cpp