Fix: ordering when dealing with camelCased field

[he0119]

Description

I found that f.name.value at L110 is camelCase value while at L63 f.name is underscore value which makes sort_key function always return 0.

https://github.com/strawberry-graphql/strawberry-graphql-django/blob/c90a7907913188cb5b70ee74e3fbe4a1ead7c8a2/strawberry_django/ordering.py#L110 https://github.com/strawberry-graphql/strawberry-graphql-django/blob/c90a7907913188cb5b70ee74e3fbe4a1ead7c8a2/strawberry_django/ordering.py#L62-L65

Try to fix it by converting f.name to camelCase value, don't know if this is the right way to fix the bug (will f.name.value always be camelCase value?).

Types of Changes

• [ ] Core
• [x] Bugfix
• [ ] New feature
• [ ] Enhancement/optimization
• [ ] Documentation

Issues Fixed or Closed by This PR

https://github.com/strawberry-graphql/strawberry-graphql-django/issues/150#issuecomment-1835527261

Checklist

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