[FLINK-39755][tests] RuntimeOpenRestAPIDocsCompletenessITCase fails for jdk 21+

[snuyanzin]

What is the purpose of the change

The reason is that starting java 21 there is SequenceCollection which brings last and first methods
On the other side ConfigurationInfo and JobRescalesHistory extend ArrayList
as a result in case of java 21 or java 25 it fails as (in case of java 11, 17 it is green)

May 25 21:18:01 21:18:01.920 [ERROR]   RuntimeOpenRestAPIDocsCompletenessITCase.testRuntimeRestApiDocsUpToDate:73 [Committed `rest_v1_dispatcher.yml` file is out of date. Please regenerate docs under `flink-docs` module based on `README.md`.] 
May 25 21:18:01 Path:
May 25 21:18:01   /__w/1/s/docs/static/generated/rest_v1_dispatcher.yml
May 25 21:18:01 and path:
May 25 21:18:01   /tmp/junit-2445394591213322851/rest_v1_dispatcher.yml
May 25 21:18:01 do not have same content:
May 25 21:18:01 
May 25 21:18:01 Missing content at line 90:
May 25 21:18:01   ["                properties:",
May 25 21:18:01    "                  first:",
May 25 21:18:01    "                    $ref: "#/components/schemas/ConfigurationInfoEntry"",
May 25 21:18:01    "                  last:",
May 25 21:18:01    "                    $ref: "#/components/schemas/ConfigurationInfoEntry""]
May 25 21:18:01 
May 25 21:18:01 Missing content at line 409:
May 25 21:18:01   ["                properties:",
May 25 21:18:01    "                  first:",
May 25 21:18:01    "                    $ref: "#/components/schemas/ConfigurationInfoEntry"",
May 25 21:18:01    "                  last:",
May 25 21:18:01    "                    $ref: "#/components/schemas/ConfigurationInfoEntry""]
May 25 21:18:01 

Brief change log

ConfigurationInfo and JobRescalesHistory

Verifying this change

java 21

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): ( no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): ( no)
• The serializers: (no)
• The runtime per-record code paths (performance sensitive): (no )
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: (no)
• The S3 file system connector: (no)

Documentation

• Does this pull request introduce a new feature? (no)
• If yes, how is the feature documented? (not applicable )

---

Was generative AI tooling used to co-author this PR?

• Yes (please specify the tool below)

[snuyanzin]

@RocMarshal would be great if you take a look since you were the one who contributed to JobRescalesHistory

[flinkbot]

CI report:

• 6ba1ff0 Azure: SUCCESS

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[RocMarshal]

Thanks @snuyanzin for the catch and fix!

LGTM +1

[snuyanzin]

thanks for taking a look