[CI] AnalyzerTests testMvAppendValidation failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic-platform-support #4546 / windows-2016_checkpart3_platform-support-windows
• elasticsearch-periodic-platform-support #4546 / rhel-8_platform-support-unix
• elasticsearch-periodic-platform-support #4546 / oraclelinux-8_platform-support-unix
• elasticsearch-periodic #4575 / openjdk17_checkpart3_java-matrix
• elasticsearch-intake #11942 / part3
• elasticsearch-intake #11939 / part3

Reproduction Line:

./gradlew ":x-pack:plugin:esql:test" --tests "org.elasticsearch.xpack.esql.analysis.AnalyzerTests.testMvAppendValidation" -Dtests.seed=56F27FB58397CF92 -Dtests.locale=fr-PF -Dtests.timezone=Pacific/Enderbury -Druntime.java=23

Applicable branches:
8.x

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

java.lang.AssertionError: 
Expected: a string containing "second argument of [mv_append(text, date)] must be [text], found value [date] type [datetime]"
     but: was "Found 1 problem
line 1:19: second argument of [mv_append(text, date)] must be [keyword], found value [date] type [datetime]"

Issue Reasons:

• [8.x] 6 failures in test testMvAppendValidation (3.5% fail rate in 171 executions)
• [8.x] 2 failures in step part3 (5.6% fail rate in 36 executions)
• [8.x] 2 failures in pipeline elasticsearch-intake (5.6% fail rate in 36 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 testMvAppendValidation (0.8% fail rate in 249 executions)
• [main] 2 failures in step part3 (3.6% fail rate in 56 executions)
• [main] 2 failures in pipeline elasticsearch-intake (3.6% fail rate in 56 executions)

Build Scans:

• elasticsearch-intake #11937 / part3
• elasticsearch-intake #11931 / part3

[elasticsearchmachine]

Pinging @elastic/es-analytical-engine (Team:Analytics)