fix bank/SendEnabled being `null` in simulations import-export

[yoongbok-lee]

Summary of the Bug

After correctly adding in the params module manager, the import-export simulation tests started failing only for the case where bank/SendEnabled param is empty. We need to debug why this happens and fix it.

Steps to Reproduce

Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior

A clear and concise description of what you expected to happen.

Screenshots

If applicable, add screenshots to help explain your problem.

Environment (please complete the following information)

• Chain Version: Git commit hash or release version.
• Golang Version:
• OS:

Additional Context

Add any other context about the problem here.

---

For Admin Use

• [ ] Not duplicate issue
• [ ] Appropriate labels applied
• [ ] Appropriate contributors tagged