Update the Windows target OS version strings to reflect system update

Windows silently updated and, because we target the exact version, the
benchmarks running on these machines started to fail with "out of
capacity" errors.

The long term solution here probably has to do with removing the OS
version from the targeting criteria altogether given the fact that we
already target the exact machines, but in the short term, this should
get our bots greener.

TBR=nednguyen@google.com

Bug: 818877
Change-Id: I95ecfc8b3381eaa45c0d69d2b0caa747d1b1f9eb
Reviewed-on: https://chromium-review.googlesource.com/963146
Commit-Queue: Ned Nguyen <nednguyen@google.com>
Reviewed-by: Ned Nguyen <nednguyen@google.com>
Reviewed-by: Charlie Andrews <charliea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543427}

tools/perf/core/perf_data_generator.py

@@ -294,7 +294,7 @@ def get_waterfall_config():
     swarming=[
       {
        'gpu': '8086:1616',
-       'os': 'Windows-10-16299.248',
+       'os': 'Windows-10',
        'pool': 'Chrome-perf',
        'device_ids': [
            'build117-b1', 'build118-b1',
@@ -308,7 +308,7 @@ def get_waterfall_config():
     swarming=[
       {
        'gpu': '102b:0534',
-       'os': 'Windows-10-10240',
+       'os': 'Windows-10',
        'pool': 'Chrome-perf',
        'device_ids': [
            'build132-m1', 'build133-m1',