cryptic crash caused by jme3-jogg library absent at runtime

Raised at the Forum/Hub: https://hub.jmonkeyengine.org/t/why-this-exception-appears/44890

Surely we can provide a more helpful diagnostic!

How to reproduce the crash:

In "jme3-examples/build.gradle", replace

implementation project(':jme3-jogg')

with

compileOnly project(':jme3-jogg')

and then run one of the audio tests, such as "TestOgg".

Typical console output, for current "master" branch:

Playing without filter
Sep 06, 2021 9:12:57 AM com.jme3.app.LegacyApplication handleError
SEVERE: Uncaught exception thrown in Thread[jME3 Main,6,main]
com.jme3.asset.AssetLoadException: No loader registered for type "ogg"
	at com.jme3.asset.ImplHandler.aquireLoader(ImplHandler.java:196)
	at com.jme3.asset.DesktopAssetManager.loadLocatedAsset(DesktopAssetManager.java:268)
	at com.jme3.asset.DesktopAssetManager.loadAsset(DesktopAssetManager.java:388)
	at com.jme3.audio.AudioNode.<init>(AudioNode.java:164)
	at com.jme3.audio.AudioNode.<init>(AudioNode.java:144)
	at jme3test.audio.TestOgg.simpleInitApp(TestOgg.java:53)

Reproduce the failure by changing the dependency in jme3-examples/build.gradle and running an audio test such as TestOgg. Start at com.jme3.asset.ImplHandler.aquireLoader, following the stack trace from DesktopAssetManager to AudioNode. Done means the missing jme3-jogg case produces a more helpful diagnostic than the current "No loader registered for type ogg" message.