Issue:
bug(user): Wrong Internal user `org_id`

Currently when an internal user is being created, a new user will be created and a `user_role` with `merchant_id` as `juspay000` will also be inserted.

As the merchant `juspay000` already has a `org_id`, we should use that and insert that `org_id` in `user_role`, but currently a new `org_id` is being generated and inserted everytime when this API is hit.

Resolution:
<think>
PR Context:
- Title: fix(users): Populate correct `org_id` for Internal Signup
- Merged: 2024-06-05T13:08:00Z
- Files changed: 2 files
- Commits: 2 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [x] Bugfix
- [ ] New feature
- [ ] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
<!-- Describe your changes in detail -->
Internal signup will now use the `org_id` of `juspay000` and insert it in `user_roles`.

### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [ ] This PR modifies application config
</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** fix(users): Populate correct `org_id` for Internal Signup (#4888)
Files to modify:


**crates/router/src/core/user.rs**
  Modify existing code

**crates/router/src/types/domain/user.rs**
  Modify existing code