[tests] enable `OT_PLATFORM_LOG_CRASH_DUMP` #1452

Job	Run time
Examples	2m 28s
Unittests	2m 54s
Stress network-forming	22m 39s
Stress commissioning	17m 7s
Stress connectivity	15m 59s
Stress network-latency	2m 45s
Stress multicast-performance	2m 22s
Stress otns-performance	2m 42s
upload-coverage	20s
	1h 9m 16s

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