Create rake task that adds custom dashboard to ops and seeds an anomaly metric

What does this MR do?

Adds a rake task to add a development_metrics.yml that seeds metrics into a custom dashboard in a project.

To test: Run bundle exec rake 'gitlab:seed:development_metrics[your project id]'

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides

#213412 (closed)