fix(deps): Migrate MFA code to our codebase and bump djangorestframework

[gagantrivedi]

Thanks for submitting a PR! Please check the boxes below:

• I have run pre-commit to check linting
• I have added information to docs/ if required so people know about the feature!
• I have filled in the "Changes" section below?
• I have filled in the "How did you test this code" section below?
• I have used a Conventional Commit title for this Pull Request

Changes

• Because Trench is no longer maintained, this commit adds all the code that we depend on.
• Bump djangorestframework
• Fixes update feature external resource endpoint

How did you test this code?

The following scenarios were tested manually:

• Generate MFA code from the old library and log in using the code from this PR and vice versa.
• Log in using the backup codes generated by the old library with the code from this PR and vice versa.

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[github-actions]

Uffizzi Preview deployment-52049 was deleted.

[matthewelwell]

@gagantrivedi this looks good to me now, I think we can resolve the merge conflicts and merge it in.