Move p_ci_templates metrics to Snowplow
Closes https://gitlab.com/gitlab-org/product-intelligence/-/issues/538
In https://gitlab.com/gitlab-org/product-intelligence/-/issues/493 we selected experimental set of metrics. Now we need to send them using Snowplow.
Metric redis_hll_counters.ci_templates.ci_templates_total_unique_counts_monthly
is an HLL metric which is aggregated from 150 underlying metrics (https://gitlab.com/gitlab-org/gitlab/-/blob/master/config/metrics/counts_28d/20210216184559_ci_templates_total_unique_counts_monthly.yml#L18).