[CI] OTLPMetricsIndexingRestIT testIngestMetricDataViaMetricExporter failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic-platform-support #10535 / debian-12_platform-support-unix
• elasticsearch-intake #28138 / part2

Reproduction Line:

./gradlew ":x-pack:plugin:otel-data:javaRestTest" --tests "org.elasticsearch.xpack.oteldata.otlp.OTLPMetricsIndexingRestIT.testIngestMetricDataViaMetricExporter" -Dtests.seed=B3792081A893F6AE -Dtests.locale=ka-GE -Dtests.timezone=Pacific/Marquesas -Druntime.java=24

Applicable branches:
main

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

java.lang.AssertionError: 
Expected: "2025-09-10T06:02:31Z"
     but: was "2025-09-10T06:02:31.000Z"

Issue Reasons:

• [main] 2 failures in test testIngestMetricDataViaMetricExporter (0.8% fail rate in 253 executions)

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

[elasticsearchmachine]

This has been muted on branch main

Mute Reasons:

• [main] 2 failures in test testIngestMetricDataViaMetricExporter (0.8% fail rate in 253 executions)

Build Scans:

• elasticsearch-periodic-platform-support #10535 / debian-12_platform-support-unix
• elasticsearch-intake #28138 / part2

[elasticsearchmachine]

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