Resolve "FogBugz - Unable to change project name"

What does this MR do and why?

This MR makes fogbugz importer respect new_name and target_namespace provided from frontend

Screenshots or screen recordings

New_Project___GitLab__2_

How to set up and validate locally

1. Open Menu -> Create new project -> Import Fogbugz
2. Use https://testimport.fogbugz.com as url, and iklymov@gitlab.com / testing as credentials
3. start import onboarding project to any other group except default and with any other name
4. observe correct group and project name when import completes

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.