Detect quote convention for file pt proj (minor fix)

[benjaminking]

Unfortunately I forgot to include FileParatextProjectQuoteConventionDetector in __init__.py, so the released version is not usable in SILNLP for quote convention detection.

(By the way, is it better to create a new branch in cases like this or just modify the already merged branch?)

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This change is 

[codecov-commenter]

Codecov Report

❌ Patch coverage is 71.42857% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.10%. Comparing base (146f195) to head (4ac7b4e).
⚠️ Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
...file_paratext_project_quote_convention_detector.py	69.23%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #226      +/-   ##
==========================================
- Coverage   91.11%   91.10%   -0.02%     
==========================================
  Files         333      334       +1     
  Lines       21706    21720      +14     
==========================================
+ Hits        19778    19788      +10     
- Misses       1928     1932       +4     

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[Enkidu93]

In general, I'd say making a new branch is the easiest/best

@Enkidu93 reviewed 2 of 2 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @benjaminking)

[Enkidu93]

I went ahead and rebased it. Like I said, if you just use a new branch, then you won't run into merge conflict issues like these (even if they're easy to resolve).