blessed-builds: Fix wrong build states

Change buildResult default to "FAILURE" as a safetey net and don't
use 'error ()' since that would abort early. This makes sure we
don't mark builds as as succesful that failed.
1 job for master in 22 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #231096
librem5
build-native

00:00:22