Add global search indexing SLI to SLI library
With gitlab-org/gitlab!97167 (merged) merged we now have the global_search_indexing_apdex
application SLI, here we start with adding it to the metrics-catalog
With gitlab-org/gitlab!97167 (merged) merged we now have the global_search_indexing_apdex
application SLI, here we start with adding it to the metrics-catalog