Truck-Factor: Warns that log4j is not initialized properly and reports no score

Hi,

for fun I tried to calculate the truck factor of vscode. I followed the usage guide, skipping the optional linguist part.

I could package the jar just fine, but when running it I got this output:

> java -jar gittruckfactor-1.0.jar ../../../vscode microsoft/vscode
log4j:WARN No appenders could be found for logger (aserg.gtf.GitTruckFactor).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

Am I doing something wrong?

Kind regards yeldiRium