[ITensors] Use QR in QN factorize

[mtfishman]

Description

Use QR in QN factorize.

[codecov-commenter]

Codecov Report

Patch coverage: 100.00% and project coverage change: -18.04% ⚠️

Comparison is base (048e69a) 85.40% compared to head (4b6f5b4) 67.37%.

❗ Current head 4b6f5b4 differs from pull request most recent head 811c0b0. Consider uploading reports for the commit 811c0b0 to get more accurate results

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Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1195       +/-   ##
===========================================
- Coverage   85.40%   67.37%   -18.04%     
===========================================
  Files          88       87        -1     
  Lines        8427     8388       -39     
===========================================
- Hits         7197     5651     -1546     
- Misses       1230     2737     +1507     

Files Changed	Coverage Δ
src/tensor_operations/matrix_decomposition.jl	91.54% <100.00%> (-0.74%)	⬇️

... and 35 files with indirect coverage changes

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[mtfishman]

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