build\build.ps1: Fixed script to fail the build if an external executable call fails.
build\build.ps1: Fixed script to fail the build if an external executable call fails.

apache/lucenenet,apache/lucenenet,apache/lucenenet,sisve/lucenenet,NightOwl888/lucenenet,laimis/lucenenet,sisve/lucenenet,jeme/lucenenet,laimis/lucenenet,jeme/lucenenet,jeme/lucenenet,apache/lucenenet,NightOwl888/lucenenet,jeme/lucenenet,NightOwl888/lucenenet,NightOwl888/lucenenet