Revert of Swarm setup_unittests on FYI bots. (patchset #2 id:40001 of https://codereview.chromium.org/1223293004/)

Reason for revert:
This seems to not work: https://chromium-swarm.appspot.com/user/task/28ace3bc39b53310

Original issue's description:
> Swarm setup_unittests on FYI bots.
>
> BUG=153829
>
> Committed: https://crrev.com/b398dec5088da75d3fbfb8d810c9b6f69ec7182a
> Cr-Commit-Position: refs/heads/master@{#338902}

TBR=maruel@chromium.org,grt@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=153829

Review URL: https://codereview.chromium.org/1239083002

Cr-Original-Commit-Position: refs/heads/master@{#339026}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 38b7fe8b254a356f7e14d28c4b4033593956e1c9

gn_migration.gypi

@@ -569,7 +569,6 @@
             ['OS=="win"', {
               'dependencies': [
                 '../chrome/chrome.gyp:installer_util_unittests_run',
-                '../chrome/chrome.gyp:setup_unittests_run',
                 '../sandbox/sandbox.gyp:sbox_integration_tests',
                 '../sandbox/sandbox.gyp:sbox_unittests',
                 '../sandbox/sandbox.gyp:sbox_validation_tests',