Android: Skip releases without valid artifacts

fetch_github_release.py supports two operations:
- latest: gets the latest release version
- get_urls: get the urls for a specific version (usually latest)

Previously only get_urls actually checked whether a specific release has
an artifact that we want and failed if it did not. Thus if the latest
release did not have the artifact we want, then latest would happily
return that release version despite knowing get_urls would fail.

This CL switches us to checking releases one by one starting with the
latest one, and returning the first release that contains the artifacts
that we want. This ensures that get_urls would not fail if latest
succeeds.

Also rename 3pp to 3pp_common so that the 3pp try bot does not get
confused by an invalid //build/3pp directory.

Bug: 1496909, 1497750
Change-Id: I240598cb8ff4c6ec54fd65af534a61517d3bbc10
Fixed: 1496909, 1497750
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4982330
Commit-Queue: Andrew Grieve <agrieve@chromium.org>
Auto-Submit: Peter Wen <wnwen@chromium.org>
Commit-Queue: Peter Wen <wnwen@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1217802}
NOKEYCHECK=True
GitOrigin-RevId: 42799d429c7d32db930958e5dc9ec26d8ef9dc7f
6 files changed