Adds utm_medium_count_distinct_of_campaign_medium custom metric

[lightdash]

Created by Lightdash, this pull request adds utm_medium_count_distinct_of_campaign_medium custom metric to the dbt model.
Triggered by user Tori Whaley (tori@lightdash.com)

⚠️ Note: Do not change the label or id of your custom metrics in this pull request. Your custom metrics will not be replaced with YAML custom metrics if you change the label or id of the custom metrics in this pull request. Lightdash requires the IDs and labels to match 1:1 in order to replace custom custom metrics with YAML custom metrics.

[github-actions]

🚀 Deployed 7417de1 to https://analytics.lightdash.cloud/projects/f32f089c-1105-4084-b1d6-6f895f2b34fc/tables