ATLASRECTS-7505: give default names for ParticleJetDeltaRLabelTool

As @christos pointed out, this tool by default was adding decorators called "" to jets. That isn't good, so I'm setting the default values to the same keys we tell the tool to use in all the python code I could find.

I'm a bit mystified about what code was setting this tool up, since everything I found was setting these keys, but oh well...