fix(@angular-devkit/architect): provide better error when builder is … #219

Job	Run time
list	39s
workflow (build-cli)	2m 8s
workflow (modules-builder-tests)	2m 31s
workflow (devkit-core-tests)	2m 4s
workflow (devkit-core-tests-rerun)	2m 6s
workflow (build-unit-tests)	2m 20s
	11m 48s

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