feat: Add ValidationError code to OperationMessage

[zvyn]

Description

Extends the OperationMessage by a code attribute that is set to the ValidationError.code if available.

I changed the test project to apply Djangos default validation in order to test that error codes used by Django internally are passed through as expected. This had the side-effect of turning a datetime object into a date object in an otherwise unrelated test.

Types of Changes

• Enhancement/optimization
• Documentation

Issues Fixed or Closed by This PR

• Provide ValidationError code in OperationMessage #356

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• I have tested the changes and verified that they work and don't break anything (as well as I can manage).

[bellini666]

This had the side-effect of turning a datetime object into a date object in an otherwise unrelated test.

Oh, I know what happened. The field is a DateField, but the argument was typed as datetime. It is actually a bug in the test that your change identified because you called .full_clean() on the model.

It is harmless though and I'll fix it later :)

[bellini666]

LGTM :)

[bellini666]

@zvyn there's just a small pyright issue that needs to be fixed, then it can be merged

[zvyn]

@bellini666 thanks for the review! I'll take a look at the pyright issue later today

[codecov-commenter]

Codecov Report

Patch coverage: 66.66% and no project coverage change.

Comparison is base (2a2723c) 87.99% compared to head (5bcdebf) 87.99%.
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #358   +/-   ##
=======================================
  Coverage   87.99%   87.99%           
=======================================
  Files          33       33           
  Lines        2940     2941    +1     
=======================================
+ Hits         2587     2588    +1     
  Misses        353      353           

Files Changed	Coverage Δ
strawberry_django/fields/types.py	86.63% <50.00%> (+0.06%)	⬆️
strawberry_django/mutations/fields.py	86.16% <100.00%> (ø)

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