[FLINK-39880][tests] Bump minikdc to 3.4.3

[snuyanzin]

What is the purpose of the change

One more step towards java 25
YARNSessionFIFOSecuredITCase fails in case of java25 with miniKDC 3.2.4
so bumping the version

Brief change log

pom

Verifying this change

java25

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

• Dependencies (does it add or upgrade a dependency): (yes )
• 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 )

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

• Yes (please specify the tool below)

[flinkbot]

CI report:

• c4a6c24 Azure: SUCCESS

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