Bump defmt from 0.3.5 to 0.3.6 in /examples/stm32f4-event-printer #80

Job	Run time
stm32f4-event-printer	2m 8s
lib (1.62.0, use_alloc)	4m 27s
lib (1.62.0, use_alloc,defmt)	4m 31s
lib (1.62.0, use_heapless)	4m 33s
lib (1.62.0, use_heapless,defmt)	4m 41s
lib (stable, use_alloc)	1m 37s
lib (stable, use_alloc,defmt)	1m 42s
lib (stable, use_heapless)	1m 42s
lib (stable, use_heapless,defmt)	1m 48s
	27m 9s

Provide feedback