fix(tests): use relative import for assert_matches_type in webhooks test (#440)

Author: declan-scale

tests/api_resources/test_webhooks.py

@@ -8,9 +8,10 @@
 import pytest
 
 from agentex import Agentex, AsyncAgentex
-from tests.utils import assert_matches_type
 from agentex.types import WebhookCreateWebhookTriggerResponse
 
+from ..utils import assert_matches_type
+
 base_url = os.environ.get("TEST_API_BASE_URL", "http://127.0.0.1:4010")