Update transforms.py according to new tranform chain of nitransforms

[AxelCouturierCIBM]

nipy/nitransforms@23a425d

Without this, we get an error like "TypeError: Input file is not in X5 format"

Changes proposed in this pull request

Documentation that should be reviewed

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 73.50%. Comparing base (5bb1cf5) to head (fd8a131).
⚠️ Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
fmriprep/utils/transforms.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3494   +/-   ##
=======================================
  Coverage   73.50%   73.50%           
=======================================
  Files          60       60           
  Lines        4582     4582           
  Branches      585      585           
=======================================
  Hits         3368     3368           
  Misses       1085     1085           
  Partials      129      129           

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