Fix JarAnalyzer warnings on Payara

[laurit]

On Payara JarAnalyzer produces a lot of warnings like

App - STDERR: [otel.javaagent 2024-02-09 17:24:41:595 +0000] [JarAnalyzer_WorkerThread-1] WARN io.opentelemetry.javaagent.shaded.instrumentation.javaagent.runtimemetrics.java8.JarAnalyzer - Error reading package for archive URL: file:/opt/payara/appserver/glassfish/modules/osgi-adapter.jar
App - STDERR: java.io.IOException: no entry name specified
App - STDERR: 	at java.base/sun.net.www.protocol.jar.JarURLConnection.getInputStream(JarURLConnection.java:160)
App - STDERR: 	at java.base/java.net.URL.openStream(URL.java:1165)
App - STDERR: 	at io.opentelemetry.javaagent.shaded.instrumentation.javaagent.runtimemetrics.java8.JarDetails.getInputStream(JarDetails.java:194)
App - STDERR: 	at io.opentelemetry.javaagent.shaded.instrumentation.javaagent.runtimemetrics.java8.JarDetails.computeDigest(JarDetails.java:180)
App - STDERR: 	at io.opentelemetry.javaagent.shaded.instrumentation.javaagent.runtimemetrics.java8.JarDetails.<init>(JarDetails.java:67)
App - STDERR: 	at io.opentelemetry.javaagent.shaded.instrumentation.javaagent.runtimemetrics.java8.JarDetails.forUrl(JarDetails.java:86)
App - STDERR: 	at io.opentelemetry.javaagent.shaded.instrumentation.javaagent.runtimemetrics.java8.JarAnalyzer.processUrl(JarAnalyzer.java:191)
App - STDERR: 	at io.opentelemetry.javaagent.shaded.instrumentation.javaagent.runtimemetrics.java8.JarAnalyzer$Worker.run(JarAnalyzer.java:175)
App - STDERR: 	at java.base/java.lang.Thread.run(Thread.java:829)

This PR works around these warnings and changes the JarAnalyzer logging so that warnings will be visible only when debug logging is enabled.