Merged PR 2898: Remove .sql in the xero__bank_transaction_denom_mart

# Description

Remove .sql in the xero__bank_transaction_denom_mart, effectively fixing the tests that were not running + removing the following warnings:

```
06:15:13  [WARNING]: Did not find matching node for patch with name 'xero__bank_transaction_denom_mart.sql' in the 'models' section of file 'models/reporting/xero/schema.yml'
06:15:14  [WARNING]: Test 'test.dwh_dbt.not_null_xero__bank_transaction_denom_mart.sql_id_line_item.70cdeb323e' (models/reporting/xero/schema.yml) depends on a node named 'xero__bank_transaction_denom_mart.sql' in package '' which was not found
06:15:14  [WARNING]: Test 'test.dwh_dbt.unique_xero__bank_transaction_denom_mart.sql_id_line_item.b85e051d2d' (models/reporting/xero/schema.yml) depends on a node named 'xero__bank_transaction_denom_mart.sql' in package '' which was not found
```

# Checklist

- [X] The edited models and dependants run properly with production data.
- [ ] The edited models are sufficiently documented. *Have not checked*
- [X] The edited models contain PK tests, and I've ran and passed them.
- [ ] I have checked for DRY opportunities with other models and docs. *Have not checked*
- [ ] I've picked the right materialization for the affected models. *Have not checked*

# Other

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

models/reporting/xero/schema.yml

@@ -1105,7 +1105,7 @@ models:
           The transaction currency is defined at the Bank Transaction level, and
           the values you see in this field should always be the same as the 
           currency of the Bank Transaction this line item belongs to.
-  - name: xero__bank_transaction_denom_mart.sql
+  - name: xero__bank_transaction_denom_mart
     description: |
       This model is a denormalized mart, which only exists for presentation 
       purposes in a PBI report.