[ITensorGaussianMPS] Fix keyword argument forwarding issue

[mtfishman]

Fix keyword argument forwarding issue exposed by the keyword argument refactor in #1226.

[mtfishman]

[test ITensorGaussianMPS] [test ITensors mps]

[github-actions]

Run ITensorGaussianMPS tests from comment trigger: succeeded ✅
https://github.com/ITensor/ITensors.jl/actions/runs/6724977636

[github-actions]

Run ITensorGaussianMPS tests from comment trigger: succeeded ✅
https://github.com/ITensor/ITensors.jl/actions/runs/6724977636

[github-actions]

Run ITensors mps tests from comment trigger: succeeded ✅
https://github.com/ITensor/ITensors.jl/actions/runs/6724977642

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (66f5d39) 85.28% compared to head (5a6fdcc) 54.43%.

❗ Current head 5a6fdcc differs from pull request most recent head 3d2db08. Consider uploading reports for the commit 3d2db08 to get more accurate results

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Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1228       +/-   ##
===========================================
- Coverage   85.28%   54.43%   -30.85%     
===========================================
  Files          89       88        -1     
  Lines        8445     8392       -53     
===========================================
- Hits         7202     4568     -2634     
- Misses       1243     3824     +2581     

see 41 files with indirect coverage changes

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[github-actions]

Run ITensors mps tests from comment trigger: succeeded ✅
https://github.com/ITensor/ITensors.jl/actions/runs/6724977642