chore(main): release 1.15.9

[release-please]

🤖 I have created a release beep boop

1.15.9 (2025-06-06)

Bug Fixes

• deps: Update the Java code generator (gapic-generator-java) to 2.59.0 (ec10233)

Dependencies

• Update dependency com.google.cloud:google-cloud-pubsub to v1.140.0 (#1871) (ea8a436)
• Update dependency com.google.cloud:google-cloud-pubsub to v1.140.1 (#1877) (eb6257f)
• Update dependency com.google.cloud:sdk-platform-java-config to v3.49.0 (#1868) (71aac46)
• Update googleapis/sdk-platform-java action to v2.59.0 (#1863) (4d76380)

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[zhumin8]

JDK 24 (ci / units (24) (pull_request)) and GraalVM 24 (GraalVM Native Image B) fail with:

[ERROR] COMPILATION ERROR : 
[INFO] -------------------------------------------------------------
[ERROR] error: An unhandled exception was thrown by the Error Prone static analysis plugin.

These will be addressed separately.

[release-please]

🤖 Created releases:

• v1.15.9

🌻

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Triggered job: cloud-devrel/client-libraries/java/java-pubsublite/release/stage (2025-06-06T15:58:09.341Z)

To trigger again, remove the autorelease: triggered label (in a few minutes).

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