POM: remove hardcoded imglib2-roi version
POM: remove hardcoded imglib2-roi version

The pom-imagej 14.0.0 parent specifies imglib2-roi 0.4.2 now,
which is newer than the previously hardcoded 0.4.1 version.

gab1one/imagej-ops,stelfrich/imagej-ops,imagej/imagej-ops