fix: preserve min_value=0 by bypassing get_test_argument truthy check

get_test_argument uses `{% if value %}` which treats 0 as falsy,
silently dropping min_value=0. Guard with an explicit `is none` check
so that 0 is preserved as a valid threshold value.

Ref: elementary-data/elementary#2177
Made-with: Cursor

Author: caterinaandreu

macros/edr/tests/test_configuration/get_anomalies_test_configuration.sql

@@ -95,9 +95,11 @@
         } %}
     {%- endif %}
 
-    {%- set min_value = elementary.get_test_argument(
-        "min_value", min_value, model_graph_node
-    ) %}
+    {%- if min_value is none %}
+        {%- set min_value = elementary.get_test_argument(
+            "min_value", none, model_graph_node
+        ) %}
+    {%- endif %}
 
     {% set anomaly_exclude_metrics = elementary.get_test_argument(
         "anomaly_exclude_metrics", anomaly_exclude_metrics, model_graph_node