Add infinite loop detection to test

From playing around deliberately introducing bugs for Hypothesis to
find, infinte looping is another failure mode its possible to introduce.
But without an explicit check for this it just results in the test
hanging which isn't that helpful.

tests/unit/utils/test_sqlalchemy_exec_utils.py

@@ -21,13 +21,25 @@ class FakeConnection:
     def __init__(self, table_data):
         self.table_data = list(table_data)
         self.random = random.Random(202412190902)
+        self.last_query = None
+        self.duplicate_query_count = 0
 
     def execute(self, query):
         self.call_count += 1
         compiled = query.compile()
         sql = str(compiled).replace("\n", "").strip()
         params = compiled.params
 
+        if self.last_query == (sql, params):  # pragma: no branch
+            self.duplicate_query_count += 1
+            if self.duplicate_query_count > 10:
+                raise RuntimeError(
+                    "Repeated duplicate queries: stuck in infinite loop?"
+                )
+        else:
+            self.last_query = (sql, params)
+            self.duplicate_query_count = 0
+
         if sql == "SELECT t.key, t.value FROM t ORDER BY t.key LIMIT :param_1":
             limit = params["param_1"]
             return self.sorted_data()[:limit]