chore: fix requestFinished event when response was null (#1086)

Co-authored-by: Axel Hörteborn <axel.horteborn@sspa.se>
Co-authored-by: Max Schmitt <max@schmitt.mx>

Author: 3 people

playwright/_impl/_browser_context.py

@@ -137,7 +137,7 @@ def __init__(
             "requestFinished",
             lambda params: self._on_request_finished(
                 from_channel(params["request"]),
-                from_nullable_channel(params["response"]),
+                from_nullable_channel(params.get("response")),
                 params["responseEndTiming"],
                 from_nullable_channel(params.get("page")),
             ),