Merged PR 4578: Propagates the month attribution from invoicing data

# Description

Following the changes of the month attribution on invoicing data depending if the document is posted on Xero or in Hyperline, this PR ensures that the 2 affected areas capture this change.

This means:
* Xero - Sales Monthly Trends
* KPIs - Invoiced Revenue

# 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: #28158

models/intermediate/xero/int_xero__sales_monthly_trends.sql

@@ -19,18 +19,18 @@ with
                 accounting_financial_l3_aggregation, 'UNSET'
             ) as accounting_financial_l3_aggregation,
             min(
-                date_trunc('month', document_issued_date_utc)::date
+                date_trunc('month', document_is_effective_at_end_of_month_utc)::date
             ) as first_invoiced_month_utc
         from int_xero__sales_denom_mart
-        where document_issued_date_utc is not null
+        where document_is_effective_at_end_of_month_utc is not null
         group by 1, 2, 3, 4, 5, 6
     ),
     unique_months as (
         select distinct
-            date_trunc('month', document_issued_date_utc)::date
+            date_trunc('month', document_is_effective_at_end_of_month_utc)::date
             as document_issued_month_utc
         from int_xero__sales_denom_mart
-        where document_issued_date_utc is not null
+        where document_is_effective_at_end_of_month_utc is not null
     ),
     category_skeleton as (
         select distinct
@@ -59,7 +59,7 @@ with
     ),
     aggregated_amount_wo_taxes_in_gbp as (
         select
-            date_trunc('month', document_issued_date_utc)::date
+            date_trunc('month', document_is_effective_at_end_of_month_utc)::date
             as document_issued_month_utc,
             coalesce(document_status, 'UNSET') as document_status,
             coalesce(document_type, 'UNSET') as document_type,
@@ -75,7 +75,7 @@ with
             ) as accounting_financial_l3_aggregation,
             sum(line_amount_wo_taxes_in_gbp) as amount_wo_taxes_in_gbp
         from int_xero__sales_denom_mart
-        where document_issued_date_utc is not null
+        where document_is_effective_at_end_of_month_utc is not null
         group by 1, 2, 3, 4, 5, 6, 7
     ),
     monthly_data_with_lag as (