sheriff: disable UkmBrowserTest.HistoryCheckDelete

This test is quite flaky.

Bug: 1131541
Change-Id: I6cd6660221b570a1e10343fa108308b3cd1a6e18
Tbr: msarda@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2425401Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809893}

chrome/browser/metrics/ukm_browsertest.cc

@@ -1094,7 +1094,8 @@ IN_PROC_BROWSER_TEST_F(UkmBrowserTest, MetricsReportingCheck) {
 // Make sure that pending data is deleted when user deletes history.
 // Keep in sync with testHistoryDelete in ios/chrome/browser/metrics/
 // ukm_egtest.mm.
-IN_PROC_BROWSER_TEST_F(UkmBrowserTest, HistoryDeleteCheck) {
+// Quite flaky: https://crbug.com/1131541
+IN_PROC_BROWSER_TEST_F(UkmBrowserTest, DISABLED_HistoryDeleteCheck) {
   ukm::UkmTestHelper ukm_test_helper(GetUkmService());
   MetricsConsentOverride metrics_consent(true);