[CI] InferenceRestIT test {p0=inference/30_semantic_text_inference/Calculates embeddings using the default ELSER 2 endpoint} failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic-platform-support #4966 / rhel-7_platform-support-unix
• elasticsearch-periodic #4977 / encryption-at-rest
• elasticsearch-periodic #4971 / concurrent-search-tests
• elasticsearch-periodic-platform-support #4947 / rhel-9_platform-support-unix
• elasticsearch-periodic-platform-support #4890 / debian-11_platform-support-unix

Reproduction Line:

./gradlew ":x-pack:plugin:inference:yamlRestTest" --tests "org.elasticsearch.xpack.inference.InferenceRestIT.test {p0=inference/30_semantic_text_inference/Calculates embeddings using the default ELSER 2 endpoint}" -Dtests.seed=57576770F7735DD4 -Dtests.locale=ia-Latn-001 -Dtests.timezone=Atlantic/Madeira -Druntime.java=23

Applicable branches:
8.16

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

java.lang.RuntimeException: Failure at [inference/30_semantic_text_inference:570]: 120.000 milliseconds timeout on connection http-outgoing-1 [ACTIVE]

Issue Reasons:

• [8.16] 5 failures in test test {p0=inference/30_semantic_text_inference/Calculates embeddings using the default ELSER 2 endpoint} (1.1% fail rate in 472 executions)
• [8.16] 3 failures in pipeline elasticsearch-periodic-platform-support (20.0% fail rate in 15 executions)
• [8.16] 2 failures in pipeline elasticsearch-periodic (13.3% fail rate in 15 executions)

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

[elasticsearchmachine]

Pinging @elastic/ml-core (Team:ML)

[Mikep86]

Muting this flaky test in all relevant branches until it is fixed: #117390