In PR #94600, we upgraded the bundled JDK to 20. However, it now appears that running ES with JDK 20 breaks APM tracing. JVM metrics are still reported, but no spans appear.

• @jamesspi reported that he couldn't see traces in Kibana after configuring APM on a branch.
• I tried configuring APM using the 8.6.2 distribution from the website, and it worked as expected
• I then tried the branch above, and no spans were reported
• I tried main, same thing.
• I tried the 8.7 branch, same thing
• I reverted commit 3b79a4f locally, to downgrade to JDK 19, and now spans were show in Kibana.