Bump log4j version to 2.25.4

[shunping]

This is to fix CVE-2026-34477.

The beam-sdks-java-io-expansion-service shaded JAR was found to contain a vulnerable version of log4j-core (2.20.0), introduced transitively via org.apache.iceberg:iceberg-aws-bundle:1.10.0.

To resolve this, the change:

1. Updates the global log4j version to 2.25.4.
2. Enforces the inclusion of the patched log4j-core in the expansion service's shaded JAR to override the version bundled in iceberg-aws-bundle.

Internal bug id: 502837070

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a security vulnerability by upgrading the log4j-core library across the project. Additionally, it ensures that the expansion service's shaded jar includes the patched version of the library, effectively mitigating a risk introduced by a transitive dependency.

Highlights

• Security Update: Updated log4j-core to version 2.25.4 to address CVE-2026-34477.
• Dependency Enforcement: Explicitly added log4j-core as a runtime dependency in the expansion-service to override a vulnerable transitive dependency found in iceberg-aws-bundle.

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[github-actions]

Checks are failing. Will not request review until checks are succeeding. If you'd like to override that behavior, comment assign set of reviewers

[shunping]

r: @Abacn

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control. If you'd like to restart, comment assign set of reviewers

[shunping]

r: @claudevdm