Switch to standardrb

[AlistairNorman]

Summary

This builds off of #6241

Checklist

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[jarednorman]

This only fixes the issues that could be automatically fixed. There's still a handful of things that couldn't be automatically addressed.

[mamhoff]

I like this change, and I think it sets us up on a good track. Why not mark it as ready for review?

[jarednorman]

I just bugged @AlistairNorman to get this wrapped when he has time. Would love to see this put to bed once and for all.

[AlistairNorman]

I'll definitely work on it but there are 94 offences that can't be automatically corrected

[codecov]

Codecov Report

❌ Patch coverage is 97.97980% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.09%. Comparing base (997f46a) to head (68afe7f).

Files with missing lines	Patch %	Lines
.../app/controllers/spree/api/checkouts_controller.rb	83.33%	1 Missing ⚠️
api/app/controllers/spree/api/orders_controller.rb	80.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6421      +/-   ##
==========================================
- Coverage   89.51%   89.09%   -0.43%     
==========================================
  Files         981      785     -196     
  Lines       20504    17318    -3186     
==========================================
- Hits        18355    15429    -2926     
+ Misses       2149     1889     -260     

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[mamhoff]

I'll definitely work on it but there are 94 offences that can't be automatically corrected

Just put them into the ignore/to-do file for now. They can be corrected later!