MNT: Apply refurb suggestions

[DimitriPapadopoulos]

• [FURB108]: Use x in (y, z) instead of x == y or x == z
• [FURB110]: Use x or y instead of x if x else y
• [FURB113]: Use x.extend(...) instead of repeatedly calling x.append()
• [FURB115]: Replace len(x) > 0 with x
• [FURB118]: Replace lambda with operator.eq
• [FURB123]: Replace int(x) with x
• [FURB125]: Return is redundant here

[effigies]

Overall looks reasonable. Thanks! Two suggestions.

[codecov]

Codecov Report

Base: 91.81% // Head: 91.84% // Increases project coverage by +0.02% 🎉

Coverage data is based on head (fe78b60) compared to base (d33a05a).
Patch coverage: 75.00% of modified lines in pull request are covered.

❗ Current head fe78b60 differs from pull request most recent head ad30f0e. Consider uploading reports for the commit ad30f0e to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1153      +/-   ##
==========================================
+ Coverage   91.81%   91.84%   +0.02%     
==========================================
  Files         101      101              
  Lines       12463    12447      -16     
  Branches     2238     2237       -1     
==========================================
- Hits        11443    11432      -11     
+ Misses        693      688       -5     
  Partials      327      327              

Impacted Files	Coverage Δ
nibabel/cmdline/dicomfs.py	19.41% <0.00%> (+0.44%)	⬆️
nibabel/cmdline/utils.py	80.64% <0.00%> (ø)
nibabel/dft.py	81.13% <ø> (-0.22%)	⬇️
nibabel/wrapstruct.py	96.99% <ø> (-0.03%)	⬇️
nibabel/deprecator.py	100.00% <100.00%> (ø)
nibabel/nicom/dicomwrappers.py	90.66% <100.00%> (ø)
nibabel/streamlines/__init__.py	100.00% <100.00%> (ø)
nibabel/streamlines/tck.py	99.48% <100.00%> (-0.01%)	⬇️

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