Merged PR 4928: KPIs Refactor Stage 3 - Expose Churn from KPIs

# Description

Small but important change.

Churn metrics will be propagated in production by sourcing intermediate/kpis rather than the cross models.

# Checklist

- [X] The edited models and dependants run properly with production data.
- [X] The edited models are sufficiently documented.
- [X] The edited models contain PK tests, and I've ran and passed them.
- [X] I have checked for DRY opportunities with other models and docs.
- [X] I've picked the right materialization for the affected models.

# Other

- [ ] Check if a full-refresh is required after this PR is merged.

Related work items: #28948

models/intermediate/cross/int_mtd_vs_previous_year_metrics.sql

@@ -163,7 +163,10 @@ with
             dimension in ('global', 'by_number_of_listings', 'by_billing_country', 'by_business_scope')
             and dimension_value <> 'UNSET'
     ),
-    int_monthly_churn_metrics as (select * from {{ ref("int_monthly_churn_metrics") }}),
+    int_kpis__agg_monthly_churn_contribution as (
+        select * 
+        from {{ ref("int_kpis__agg_monthly_churn_contribution") }}
+    ),
     int_kpis__agg_dates_main_kpis as (
         select *
         from {{ ref("int_kpis__agg_dates_main_kpis") }}
@@ -423,7 +426,7 @@ with
             and d.dimension = host_resolutions.dimension
             and d.dimension_value = host_resolutions.dimension_value
         left join
-            int_monthly_churn_metrics churn
+            int_kpis__agg_monthly_churn_contribution churn
             on d.date = churn.date
             and d.dimension = churn.dimension
             and d.dimension_value = churn.dimension_value