Unable to Test OAuth2 Workflow Locally Due to Fixed `redirect_uri` Constraint

## **Description**
I am working on integrating the OAuth2 workflow for publishing new instrument names/images to Wikidata. While implementing the workflow, I encountered an issue with the `redirect_uri`:

- The application is currently developing locally (e.g., `http://localhost:8000`).
- Wikidata cannot redirect to `localhost`, as it requires a publicly accessible URL for the `redirect_uri`, which is `https://vim.simssa.ca/oauth/callback`. (This uri was registered when I applied for the OAuth2 consumer, and can not be changed.) Here is the screenshot of the approved OAuth2 consumer:

## **Steps to Reproduce**
1. In UMIL's `instrument list` page, when users try to add new instrument names directly to wikidata, they will click on a `Authorize` button.
2. Initiate the OAuth2 flow to redirect users to the Wikidata authorization endpoint.
3. After granting permission, Wikidata attempts to redirect to the fixed `redirect_uri` (`https://vim.simssa.ca/oauth/callback`), which is inaccessible when developing locally.

## **Questions**
- Are there any recommended ways to test the OAuth2 workflow locally without modifying the fixed `redirect_uri`?
- Is there a development-friendly approach to handle this situation?