Use SciJava Common tests JAR

The TestUtils migrated from ImageJ core to SciJava Common:
https://github.com/scijava/scijava-common/commit/3aa51f812fef19cd14e3adea4d4aa5e3b395f1ea
WIP: Migrate to ImageJ Common component

See:
https://github.com/imagej/imagej-common