revert test_udfs to fix schema error.

tests/generic/test_udf.sql

@@ -1,39 +1,12 @@
 {% test test_udf(model, column_name, args, assertions) %}
     {#
         This is a generic test for UDFs.
-        The udfs are deployed using ephemeral models, as of dbt-core > 1.8
-        we need to use `this.identifier` to extract the schema from for base_test_udf().
+        The udfs are deployed using ephemeral models, so we need to
+        use the ephemeral model name to get the udf name.
      #}
-    
-    {% set schema = none %}
-    
-    {% if execute %}
-        {# Extract schema based on standard pattern `test__<schema_name>_<test_name> #}
-        {% set test_identifier = this.identifier %}
-        
-        {% if test_identifier.startswith('test_') %}
-            {% set test_identifier = test_identifier[5:] %}
-        {% endif %}
-        
-        {# Handle schemas with underscore prefix #}
-        {% if test_identifier.startswith('_') %}
-            {# For identifiers like _utils_<test_name> #}
-            {% set parts = test_identifier.split('_') %}
-            {% if parts | length > 2 %}
-                {% set schema = '_' ~ parts[1] %}
-            {% else %}
-                {% set schema = parts[0] %}
-            {% endif %}
-        {% else %}
-            {# For identifiers without underscore prefix #}
-            {% set parts = test_identifier.split('_') %}
-            {% if parts | length > 0 %}
-                {% set schema = parts[0] %}
-            {% endif %}
-        {% endif %}
-    {% endif %}
-    
-    {% set udf = schema ~ "." ~ column_name %}
+    {%- set schema = model | replace("__dbt__cte__", "") -%}
+    {%- set schema = schema.split("__") | first -%}
+    {%- set udf = schema ~ "." ~ column_name -%}
 
     {{ base_test_udf(model, udf, args, assertions) }}
-{% endtest %}
+{% endtest %}