test: use db.before_commit

frappe/database/database.py

@@ -976,7 +976,6 @@ class Database:
 
 	def commit(self):
 		"""Commit current transaction. Calls SQL `COMMIT`."""
-		# Invalidated by a commit.
 		self.before_rollback.reset()
 		self.after_rollback.reset()
 

frappe/tests/utils.py

@@ -32,7 +32,7 @@ class FrappeTestCase(unittest.TestCase):
 		# flush changes done so far to avoid flake
 		frappe.db.commit()
 		if cls.SHOW_TRANSACTION_COMMIT_WARNINGS:
-			frappe.db.add_before_commit(_commit_watcher)
+			frappe.db.before_commit.add(_commit_watcher)
 
 		# enqueue teardown actions (executed in LIFO order)
 		cls.addClassCleanup(_restore_thread_locals, copy.deepcopy(frappe.local.flags))