This might help fix the bots, which are broken in e.g.,
https://build.chromium.org/p/tryserver.v8/builders/v8_mac_rel_ng_triggered/builds/14011

The archive was added in order to transmit test262 tests more rapidly.
It doesn't serve much of a purpose for local-tests. I naively added
local-tests there out of symmetry. However, the BUILD.gn file does not
regenerate an archive when files are only deleted and not added or
changed. Since the performance concern is not present for the small
volume of local-tests, this patch reverts to the more normal mechanism
for sending over dependencies, with test262.isolate.

R=adamk

Review-Url: https://codereview.chromium.org/2643983002
Cr-Commit-Position: refs/heads/master@{#42485}