[CI] MixedClusterEsqlSpecIT test {string.LucenePushdownMixOrAnd SYNC} failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic #6948 / 8.11.4_bwc
• elasticsearch-periodic #6941 / 8.14.3_bwc
• elasticsearch-periodic #6941 / 8.11.4_bwc
• elasticsearch-periodic #6941 / 8.12.2_bwc

Reproduction Line:

./gradlew ":x-pack:plugin:esql:qa:server:mixed-cluster:v8.11.4#javaRestTest" -Dtests.class="org.elasticsearch.xpack.esql.qa.mixed.MixedClusterEsqlSpecIT" -Dtests.method="test {string.LucenePushdownMultipleAnd SYNC}" -Dtests.seed=25A509DC24C046BA -Dtests.bwc=true -Dtests.locale=smn -Dtests.timezone=CNT -Druntime.java=24

Applicable branches:
8.x

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

org.elasticsearch.client.ResponseException: method [POST], host [http://[::1]:45137], URI [/_query?format=yaml&pretty=true&error_trace=true], status line [HTTP/1.1 400 Bad Request]
---
error:
  root_cause:
  - type: "parsing_exception"
    reason: "line 1:15: mismatched input 'metadata' expecting {<EOF>, PIPE, COMMA,\
      \ OPENING_BRACKET}"
    stack_trace: "org.elasticsearch.xpack.esql.parser.ParsingException: line 1:15:\
      \ mismatched input 'metadata' expecting {<EOF>, PIPE, COMMA, OPENING_BRACKET}\n\
      \tat org.elasticsearch.xpack.esql.parser.EsqlParser$1.syntaxError(EsqlParser.java:109)\n\
      \tat org.antlr.v4.runtime.ProxyErrorListener.syntaxError(ProxyErrorListener.java:41)\n\
      \tat org.antlr.v4.runtime.Parser.notifyErrorListeners(Parser.java:544)\n\tat\
      \ org.antlr.v4.runtime.DefaultErrorStrategy.reportInputMismatch(DefaultErrorStrategy.java:327)\n\
      \tat org.antlr.v4.runtime.DefaultErrorStrategy.reportError(DefaultErrorStrategy.java:139)\n\
      
[truncated]

Issue Reasons:

• [8.x] 2 consecutive failures in step 8.11.4_bwc
• [8.x] 4 failures in test test {string.LucenePushdownMixOrAnd SYNC} (4.2% fail rate in 96 executions)
• [8.x] 2 failures in step 8.11.4_bwc (100.0% fail rate in 2 executions)
• [8.x] 2 failures in pipeline elasticsearch-periodic (100.0% fail rate in 2 executions)

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

[elasticsearchmachine]

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

[idegtiarenko]

Fixed by #124625