[CI] FullClusterRestartIT testSearch {cluster=OLD} failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic #11064 / 7.4.2_bwc
• elasticsearch-periodic #11064 / 7.5.2_bwc
• elasticsearch-periodic #11057 / 7.4.2_bwc
• elasticsearch-periodic #11057 / 7.5.2_bwc
• elasticsearch-periodic #11050 / 7.4.2_bwc
• elasticsearch-periodic #11050 / 7.5.2_bwc
• elasticsearch-periodic #11043 / 7.5.2_bwc
• elasticsearch-periodic #11043 / 7.4.2_bwc
• elasticsearch-periodic #11036 / 7.4.2_bwc
• elasticsearch-periodic #11036 / 7.5.2_bwc

Reproduction Line:

./gradlew ":qa:full-cluster-restart:v7.5.2#bwcTest" -Dtests.class="org.elasticsearch.upgrades.FullClusterRestartIT" -Dtests.method="testShrink {cluster=OLD}" -Dtests.seed=AAF6B03C6B50CFF9 -Dtests.bwc=true -Dtests.locale=tzm-Latn-MA -Dtests.timezone=America/Costa_Rica -Druntime.java=25

Applicable branches:
8.19

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

org.elasticsearch.client.WarningFailureException: method [PUT], host [http://[::1]:34287], URI [/testshrink/_settings], status line [HTTP/1.1 200 OK]
Warnings: [[processors] setting was deprecated in Elasticsearch and will be removed in a future release! See the breaking changes documentation for the next major version.]
{"acknowledged":true}

Issue Reasons:

• [8.19] 14 consecutive failures in step 7.4.2_bwc
• [8.19] 14 consecutive failures in step 7.5.2_bwc
• [8.19] 28 failures in test testSearch {cluster=OLD} (3.5% fail rate in 791 executions)
• [8.19] 14 failures in step 7.4.2_bwc (100.0% fail rate in 14 executions)
• [8.19] 14 failures in step 7.5.2_bwc (100.0% fail rate in 14 executions)
• [8.19] 14 failures in pipeline elasticsearch-periodic (100.0% fail rate in 14 executions)

Note:
This issue was created using new test triage automation. Please report issues or feedback to es-delivery.

[elasticsearchmachine]

Pinging @elastic/es-delivery (Team:Delivery)

[jozala]

This is a new issue. I've closed it, because I thought it is related to lucene compat tests. Reopening.
Same as #135969