update fastboot and ember-try to fix CI #351

Job	Run time
Percy Tests	2m 47s
Tests	3m 5s
Floating Dependencies	1m 51s
ember-canary - Allowed to fail	2m 29s
ember-lts-3.28	2m 34s
ember-release-no-deprecations - Allowed to fail	2m 50s
ember-release	2m 24s
ember-beta	2m 33s
ember-classic	2m 27s
ember-default-with-jquery	2m 34s
embroider-safe	2m 33s
embroider-optimized	2m 31s
no-deprecations	2m 34s
	33m 12s

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