Resolve "Move Support SLA Metric"
Issue
Closes #4385 (closed)
Part of: https://gitlab.com/gitlab-data/analytics/issues/1241
Solution
This MR:
- removes the SLA definition and formula from the OpMetrics page
- adds the SLA definition and formula to the Support page of the handbook + adds a link to the relevant periscope dashboard
- updates the data team links for that definition
Edited by Emilie Schario