InternalEngineTests testShouldPeriodicallyFlushAfterMerge failure

[davidkyle]

java.lang.AssertionError: 
Expected: <false>
     but: was <true>
	at __randomizedtesting.SeedInfo.seed([D9AEEA268A616C55:DFF296783E7FFD87]:0)
	at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:18)
	at org.junit.Assert.assertThat(Assert.java:956)
	at org.junit.Assert.assertThat(Assert.java:923)
	at org.elasticsearch.index.engine.InternalEngineTests.testShouldPeriodicallyFlushAfterMerge(InternalEngineTests.java:5127)

https://elasticsearch-ci.elastic.co/job/elastic+elasticsearch+7.5+matrix-java-periodic/ES_RUNTIME_JAVA=corretto11,nodes=general-purpose/236/console
https://gradle-enterprise.elastic.co/s/k5bsk266lz67c

Reproduce

./gradlew ':server:test' --tests "org.elasticsearch.index.engine.InternalEngineTests.testShouldPeriodicallyFlushAfterMerge" \
  -Dtests.seed=D9AEEA268A616C55 \
  -Dtests.security.manager=true \
  -Dtests.locale=ky \
  -Dtests.timezone=Etc/GMT-14 \
  -Dcompiler.java=12 \
  -Druntime.java=11

[elasticmachine]

Pinging @elastic/es-distributed (:Distributed/Engine)