Using deprecation in sentry-log4j2

[runningcode]

When bumping log4j2 from log4j2 from 2.20.0 to 2.26.0

> Compilation failed; see the compiler output below.
  /home/runner/work/sentry-java/sentry-java/sentry-log4j2/src/main/java/io/sentry/log4j2/SentryAppender.java:44: warning: [deprecation] ThrowableProxy in org.apache.logging.log4j.core.impl has been deprecated
  import org.apache.logging.log4j.core.impl.ThrowableProxy;
                                     
  1 error
  3 warnings

https://github.com/getsentry/sentry-java/actions/runs/25841919902/job/75928866128?pr=5435

[linear-code]

JAVA-514