BUG: Increase and limit itksoftwareguide-dashboard build parallelism
BUG: Increase and limit itksoftwareguide-dashboard build parallelism

For the ITKSoftware CircleCI builds, this increases the number of compile jobs
to 10. The use off CMAKE_JOB_POOLS also passes the jobs to ExternalProjects,
which prevents too many processes on the CI system, which has many cores and
exhausts available memory.

InsightSoftwareConsortium/ITKDevelopmentEnvironment,InsightSoftwareConsortium/ITKDevelopmentEnvironment