[BSC]: Implement BoundSessionRefreshCookieFetcherImpl

This CL implements `BoundSessionRefreshCookieFetcherImpl` that does the
network request to the rotation endpoint. Proper error handling will be
added in a follow-up CL.

Bug: b/273920907
Change-Id: I9ddaab0c640d3547ee7b81de93a7c06876bd0a10
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4509334
Auto-Submit: Monica Basta <msalama@chromium.org>
Commit-Queue: Alex Ilin <alexilin@chromium.org>
Reviewed-by: Christian Dullweber <dullweber@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1143182}
NOKEYCHECK=True
GitOrigin-RevId: c5b33d5f99f3a16e4d4c3d52959dfb7c7e45d01e
2 files changed