[Sheriff] Mark system_health.memory_desktop/browse:news:nytimes:2018 flaky

TBR=ellyjones@chromium.org

Bug: 956191
Change-Id: I335e377a40aa937917f95a799e6609c0b2489afe
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2159422Reviewed-by: Collin Baker <collinbaker@chromium.org>
Commit-Queue: Collin Baker <collinbaker@chromium.org>
Cr-Commit-Position: refs/heads/master@{#761110}

tools/perf/expectations.config

@@ -349,6 +349,7 @@ crbug.com/1017244 [ desktop ] system_health.memory_desktop/browse_accessibility:
 crbug.com/1017346 [ desktop ] system_health.memory_desktop/browse:media:youtube:2019 [ Skip ]
 crbug.com/1042632 [ win ] system_health.memory_desktop/load:tools:gmail:2019 [ Skip ]
 crbug.com/1042632 [ win ] system_health.memory_desktop/browse:social:tumblr_infinite_scroll:2018 [ Skip ]
+crbug.com/956191 [ win7 ] system_health.memory_desktop/browse:news:nytimes:2018 [ Skip ]
 
 # Memory dumps don't work at the moment for Google Earth, see the issue.
 crbug.com/1057035 system_health.memory_desktop/browse:tools:earth:2020 [ Skip ]