Adapt remix-themes for react-router-v7

[Moonnz]

Summary

This pull request introduces a simple adaptation to support React Router v7.

Changes Made

• Adjusted the code to ensure compatibility with React Router v7.

Notes

• The application itself has not been updated or tested extensively with these changes. Further work may be required to ensure full compatibility.

Next Steps

• Review the changes for correctness.
• Consider testing the application thoroughly to identify any issues related to the migration.

[Moonnz]

Failed but unrelated to the code:

This request has been automatically failed because it uses a deprecated version of `actions/upload-artifact: v2`. Learn more: https://github.blog/changelog/2024-02-13-deprecation-notice-v1-and-v2-of-the-artifact-actions/

[abereghici]

Thanks @Moonnz for this pull request! I noticed the unit tests are not working and I decided to refactor this package from scratch using the latest dependency versions. I created a new MR based on yours here : #49

Could you please review it when you have some time? Thanks!

[abereghici]

I will close this MR as we released already the react-router v7 support. Thanks @Moonnz for this MR, it was really helpful for package refactoring.