Update to Machine 3.9.3

[Enkidu93]

Also, use new Machine book confidence utility.

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This change is 

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.74%. Comparing base (d6cbc4b) to head (7df82f9).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1038      +/-   ##
==========================================
- Coverage   72.75%   72.74%   -0.01%     
==========================================
  Files         392      392              
  Lines       21711    21711              
  Branches     2820     2820              
==========================================
- Hits        15795    15793       -2     
- Misses       4793     4795       +2     
  Partials     1123     1123              

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[ddaspit]

@ddaspit reviewed 5 files and all commit messages, and made 2 comments.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on Enkidu93 and pmachapman).

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src/Serval/src/Serval.Translation/Utils/PretranslationConfidenceEvaluator.cs line 1 at r1 (raw file):

using SIL.Machine.QualityEstimation;

Nit: This should be in the global usings.

[Enkidu93]

@Enkidu93 made 1 comment.
Reviewable status: 4 of 9 files reviewed, 1 unresolved discussion.

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src/Serval/src/Serval.Translation/Utils/PretranslationConfidenceEvaluator.cs line 1 at r1 (raw file):

Previously, ddaspit (Damien Daspit) wrote…

Nit: This should be in the global usings.

OK, my instinct was to have it in the global usings, but the other neighboring classes also had their imports from SIL.Machine non-global. I've gone ahead and updated them too.