We don't build with bundled sysroot on gcc builders, hence we need to
match the sysroot on tester bots. There is already a number of
Focal bots in chromium.tests and the capacity needed for these gcc
bots is insignificant.

No-Try: true
Bug: chromium:1307180
Change-Id: Id9d3d08bdb09923cf919b17286c949c6ac9005ed
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3747872Reviewed-by: Alexander Schulze <alexschulze@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81563}