[CI] FullClusterRestartIT.testSnapshotRestore breaks other tests by wiping out persistent tasks #36816
Description
https://elasticsearch-ci.elastic.co/job/elastic+elasticsearch+master+intake/867/console
Reproduces for me with a variety of seeds.
/gradlew :x-pack:qa:full-cluster-restart:with-system-key:v6.6.0#upgradedClusterTestRunner \
-Dtests.seed=A29E5A089272CB0C \
-Dtests.class=org.elasticsearch.xpack.restart.MlMigrationFullClusterRestartIT \
-Dtests.method="testMigration" \
-Dtests.security.manager=true -Dtests.locale=ms -Dtests.timezone=America/Araguaina \
-Dcompiler.java=11 -Druntime.java=8
MlMigrationFullClusterRestartIT.testMigration <<< FAILURES!
> Throwable #1: java.lang.AssertionError
> at __randomizedtesting.SeedInfo.seed([655FBD85FBD8974E:A6E3BD79B4BC8D2D]:0)
> at org.elasticsearch.xpack.restart.MlMigrationFullClusterRestartIT.lambda$waitForMigration$2(MlMigrationFullClusterRestartIT.java:167)
> at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:847)
> at org.elasticsearch.xpack.restart.MlMigrationFullClusterRestartIT.waitForMigration(MlMigrationFullClusterRestartIT.java:159)
> at org.elasticsearch.xpack.restart.MlMigrationFullClusterRestartIT.upgradedClusterTests(MlMigrationFullClusterRestartIT.java:109)
> at org.elasticsearch.xpack.restart.MlMigrationFullClusterRestartIT.testMigration(MlMigrationFullClusterRestartIT.java:77)
> at java.lang.Thread.run(Thread.java:745)
> Suppressed: java.lang.AssertionError
> at org.elasticsearch.xpack.restart.MlMigrationFullClusterRestartIT.lambda$waitForMigration$2(MlMigrationFullClusterRestartIT.java:167)
> at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:835)
> ... 40 more
> Suppressed: java.lang.AssertionError
> at org.elasticsearch.xpack.restart.MlMigrationFullClusterRestartIT.lambda$waitForMigration$2(MlMigrationFullClusterRestartIT.java:167)
> at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:835)
> ... 40 more
I'm going to mute the test.