[CI] MixedClusterEsqlSpecIT test {ip.ToIpInAgg SYNC} failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic #8893 / 8.12.2_bwc
• elasticsearch-periodic #8887 / 8.12.2_bwc
• elasticsearch-periodic #8881 / 8.11.4_bwc
• elasticsearch-periodic #8875 / 8.12.2_bwc
• elasticsearch-periodic #8869 / 8.12.2_bwc
• elasticsearch-periodic #8863 / 8.12.2_bwc
• elasticsearch-periodic #8857 / 8.11.4_bwc
• elasticsearch-periodic #8857 / 8.12.2_bwc
• elasticsearch-periodic #8851 / 8.12.2_bwc

Reproduction Line:

./gradlew ":x-pack:plugin:esql:qa:server:mixed-cluster:v8.12.2#javaRestTest" -Dtests.class="org.elasticsearch.xpack.esql.qa.mixed.MixedClusterEsqlSpecIT" -Dtests.method="test {ip.ToIpInAgg SYNC}" -Dtests.seed=703C5C97A5661337 -Dtests.bwc=true -Dtests.locale=cgg-Latn-UG -Dtests.timezone=America/Thunder_Bay -Druntime.java=24

Applicable branches:
8.19

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

org.elasticsearch.client.ResponseException: method [POST], host [http://[::1]:35445], URI [/_query?format=cbor&pretty=true&error_trace=true], status line [HTTP/1.1 400 Bad Request]
¿eerror¿jroot_cause�¿dtypeqparsing_exceptionfreasonxCline 1:42: mismatched input '=' expecting {<EOF>, PIPE, COMMA, '.'}kstack_tracey	®org.elasticsearch.xpack.esql.parser.ParsingException: line 1:42: mismatched input '=' expecting {<EOF>, PIPE, COMMA, '.'}
	at org.elasticsearch.xpack.esql.parser.EsqlParser$1.syntaxError(EsqlParser.java:109)
	at org.antlr.v4.runtime.ProxyErrorListener.syntaxError(ProxyErrorListener.java:41)
	at org.antlr.v4.runtime.Parser.notifyErrorListeners(Parser.java:544)
	at org.antlr.v4.runtime.DefaultErrorStrategy.reportInputMismatch(DefaultErrorStrategy.java:327)
	at org.antlr.v4.runtime.DefaultErrorStrategy.reportError(DefaultErrorStrategy.java:139)
	at org.elasticsearch.xpack.esql.parser.EsqlBaseParser.singleStatement(EsqlBaseParser.java:188)
	at org.elasticsearch.xpack.esql.parser.
[truncated]

Issue Reasons:

• [8.19] 2 consecutive failures in step 8.12.2_bwc
• [8.19] 9 failures in test test {ip.ToIpInAgg SYNC} (4.4% fail rate in 203 executions)
• [8.19] 7 failures in step 8.12.2_bwc (87.5% fail rate in 8 executions)
• [8.19] 2 failures in step 8.11.4_bwc (25.0% fail rate in 8 executions)
• [8.19] 8 failures in pipeline elasticsearch-periodic (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-analytical-engine (Team:Analytics)