FIX: DWIPreproc issue

[GalKepler]

Summary

Just a small fix in MRtrix3's DWIPreproc class - referencing out_grad_mrtrix instead of export_grad_mrtrix in the _list_outputs method of the class.

Fixes #3595.

List of changes proposed in this PR (pull-request)

• Fixed DWIPreproc class.

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (ca27e51) 63.17% compared to head (7420058) 63.17%.
Report is 3 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3596   +/-   ##
=======================================
  Coverage   63.17%   63.17%           
=======================================
  Files         308      308           
  Lines       40813    40813           
  Branches     5654     5654           
=======================================
  Hits        25784    25784           
  Misses      14016    14016           
  Partials     1013     1013           

Files Changed	Coverage Δ
nipype/interfaces/mrtrix3/preprocess.py	79.86% <0.00%> (ø)

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[effigies]

Looks good. Thanks!

[GalKepler]

Sure. Just noticed that export_grad_fsl is also referenced instead of out_grad_fsl. Fixed it.