[Workbench] Hide busy/idle nodes display when crunch1 is not active
The busy/idle nodes display on the dashboard is supposed to be hidden when it would be wrong/misleading, i.e., when info[slurm_state] is not updated in the nodes table because crunch_dispatch.rb is not running.
Currently, it's hidden when the crunch1 APIs are completely disabled (pipeline_instances.index API doesn't exist). This is true for a site that has never used crunch1, but it's not true for a site that has migrated to crunch2, isn't running crunch_dispatch.rb, but still allows users to view their old crunch1 pipelines/jobs.
The condition in source:apps/workbench/app/views/projects/_show_dashboard.html.erb could be changed:
- if !PipelineInstance.api_exists?(:index) + if !PipelineInstance.api_exists?(:create)