[BUG] {p0=indices.delete_index_template/10_basic/Delete index template which is not used by data stream but index pattern matches} is flaky

[gaobinlong]

Describe the bug

org.opensearch.backwards.MixedClusterClientYamlTestSuiteIT.test {p0=indices.delete_index_template/10_basic/Delete index template which is not used by data stream but index pattern matches} is flaky:

java.lang.AssertionError: Failure at [indices.delete_index_template/10_basic:2]: got unexpected warning header [
	299 OpenSearch-2.17.0-SNAPSHOT-8d664b338ba19022eb79cc584b423665ea8915ee "index template [test_template_1] has index patterns [test-*] matching patterns from existing older templates [global] with patterns (global => [*]); this template [test_template_1] will take precedence during new index creation"
]

https://build.ci.opensearch.org/job/gradle-check/44183/

Related component

Indexing

To Reproduce

./gradlew ':qa:mixed-cluster:v2.17.0#mixedClusterTest' --tests "org.opensearch.backwards.MixedClusterClientYamlTestSuiteIT" -Dtests.method="test {p0=indices.delete_index_template/10_basic/Delete index template which is not used by data stream but index pattern matches}"

Expected behavior

Fix the flaky test

Additional Details

No response