[CI] XPackRestIT test {p0=data_stream/140_data_stream_aliases/Create data stream alias} failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-intake #19345 / rest-compat
• elasticsearch-periodic-platform-support #6771 / ubuntu-2004-aarch64_checkrestcompat_platform-support-arm
• elasticsearch-periodic-platform-support #6755 / almalinux-8-aarch64_checkrestcompat_platform-support-arm

Reproduction Line:

./gradlew ":x-pack:plugin:yamlRestTestV7CompatTest" --tests "org.elasticsearch.xpack.test.rest.XPackRestIT.test {p0=data_stream/140_data_stream_aliases/Create data stream alias}" -Dtests.seed=8463DBEC451ADCAD -Dtests.locale=os-Cyrl-GE -Dtests.timezone=America/Miquelon -Druntime.java=23

Applicable branches:
8.x

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

java.lang.AssertionError: Failure at [data_stream/140_data_stream_aliases:115]: got unexpected warning header [
	299 Elasticsearch-8.19.0-5c34bfb1f3a5a8db92b268e9ef0575946ae8a681 "this request accesses system indices: [.security-7], but in a future major version, direct access to system indices will be prevented by default"
]

Issue Reasons:

• [8.x] 3 failures in test test {p0=data_stream/140_data_stream_aliases/Create data stream alias} (3.5% fail rate in 85 executions)
• [8.x] 2 failures in pipeline elasticsearch-periodic-platform-support (66.7% fail rate in 3 executions)

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

[elasticsearchmachine]

Pinging @elastic/es-search-relevance (Team:Search Relevance)

[elasticsearchmachine]

Pinging @elastic/es-data-management (Team:Data Management)

[nielsbauman]

@slobodanadamovic this is another result of #120323. I'm a little bit surprised that the data stream tests are run by XPackRestIT, but maybe that's because it's yamlRestTestV7CompatTest. Maybe we should still include the changes you made to 140_data_stream_aliases in https://github.com/elastic/elasticsearch/pull/121296/files#diff-96a96d7b4a3705c731be1d262a009ef12d083b0c8431470f69d6fed07b094f9e after all? What do you think?

[slobodanadamovic]

@nielsbauman Thanks for the ping! Yeah, I think we should adapt these. I'll raise a PR to address this.