[CI] MappingStatsTests testToXContent failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic-platform-support #11466 / rhel-10_platform-support-unix
• elasticsearch-periodic-platform-support #11467 / rhel-10_platform-support-unix
• elasticsearch-periodic-platform-support #11465 / rhel-10_platform-support-unix
• elasticsearch-periodic-platform-support #11461 / rhel-10_platform-support-unix
• elasticsearch-periodic-platform-support #11457 / rhel-10_platform-support-unix
• elasticsearch-periodic-platform-support #11453 / rhel-10_platform-support-unix
• elasticsearch-periodic-platform-support #11449 / rhel-10_platform-support-unix
• elasticsearch-periodic-platform-support #11445 / rhel-10_platform-support-unix

Reproduction Line:

./gradlew ":server:test" --tests "org.elasticsearch.action.admin.cluster.stats.MappingStatsTests.testToXContentWithSomeSharedMappings" -Dtests.seed=F2F9CCA2F0360469 -Dtests.locale=it-IT -Dtests.timezone=Asia/Hebron -Druntime.java=25

Applicable branches:
main

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

org.junit.ComparisonFailure: expected:<...d_mapping_size" : "5[19b",
    "total_deduplicated_mapping_size_in_bytes" : 519],
    "field_types" ...> but was:<...d_mapping_size" : "5[21b",
    "total_deduplicated_mapping_size_in_bytes" : 521],
    "field_types" ...>

Issue Reasons:

• [main] 8 consecutive failures in step rhel-10_platform-support-unix
• [main] 2 consecutive failures in pipeline elasticsearch-periodic-platform-support
• [main] 8 failures in test testToXContent (0.9% fail rate in 913 executions)
• [main] 8 failures in step rhel-10_platform-support-unix (100.0% fail rate in 8 executions)
• [main] 8 failures in pipeline elasticsearch-periodic-platform-support (100.0% fail rate in 8 executions)

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

[elasticsearchmachine]

Pinging @elastic/es-storage-engine (Team:StorageEngine)

[kkrik-es]

This only happens in rhel-10_platform-support-unix, and started right after #137640 . I wonder if this is due to jvm being different, @brianseeders fyi.