Related to https://github.com/microsoft/playwright/issues/19621
Adds some instrumentation to collect timings for `APIRequestContext`
requests and adds them to the HAR trace. Doesn't yet expose them via an
API, but makes our `Duration` field in the trace viewer show a nice
duration:
<img width="1392" alt="Screenshot 2024-09-14 at 11 46 04"
src="https://github.com/user-attachments/assets/8020382d-9494-4634-9cfd-22b6f4a1d770">
I'm gonna add it to our API in a separate PR.
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Signed-off-by: Simon Knott <info@simonknott.de>
Co-authored-by: Dmitry Gozman <dgozman@gmail.com>
751b939d3a