Fix checking of resolved outputs in DefaultModuleService

[imagejan]

The method DefaultModuleService#getSingleItem is used for both inputs and outputs, but this line only checks the input:

scijava-common/src/main/java/org/scijava/module/DefaultModuleService.java

Line 498 in beb6de2

if (module.isInputResolved(name)) continue; // skip resolved inputs

See also #423 (comment).