Fix assertImageEquals to actually assert
Fix assertImageEquals to actually assert

When using pairedForEach directly, assertImageEquals(RAI, RAI) would never assert anything.
We need to call the three-argument signature assertImageEquals(RAI, RAI, BiPredicate) that adds the assertion.

imagej/imagej-legacy,imagej/imagej-legacy,imagej/imagej-legacy,imagej/imagej-legacy