[SPARK-53851] Set io.netty.noUnsafe to true to avoid JEP-498 warnings

[dongjoon-hyun]

What changes were proposed in this pull request?

This PR aims to set io.netty.noUnsafe to true to avoid JEP-498 warnings.

Why are the changes needed?

Java 24 has started to print warnings when sub.misc.Unsafe is used to access memory.

• https://openjdk.org/jeps/498

Since Netty 4.1.120.Final, we can use io.netty.noUnsafe setting.

• Disable sun.misc.Unsafe by default on Java 24+ netty/netty#14943

Does this PR introduce any user-facing change?

No behavior change.

How was this patch tested?

Manually tests.

BEFORE

Starting Operator...
WARNING: A terminally deprecated method in sun.misc.Unsafe has been called
WARNING: sun.misc.Unsafe::allocateMemory has been called by io.netty.util.internal.PlatformDependent0$2 (file:/opt/spark-operator/operator/spark-kubernetes-operator.jar)
WARNING: Please consider reporting this to the maintainers of class io.netty.util.internal.PlatformDependent0$2
WARNING: sun.misc.Unsafe::allocateMemory will be removed in a future release
25/10/09 03:35:46 INFO   o.a.s.k.o.SparkOperator Configuring operator with 50 reconciliation threads.

AFTER

Starting Operator...
25/10/09 03:32:21 INFO   o.a.s.k.o.SparkOperator Configuring operator with 50 reconciliation threads.

Was this patch authored or co-authored using generative AI tooling?

No.

[dongjoon-hyun]

Thank you, @viirya . Merged to main.