BED-5369: Added back data-testid attributes

[specter-flq]

Description

Added back the data-testid attributes to the nav bar items to ensure we don't break existing functionality that depends on it.

Motivation and Context

This PR addresses: BED-5369

How Has This Been Tested?

Manually and updated FE tests.

Types of changes

• Chore (a change that does not modify the application functionality)
• Bug fix (non-breaking change which fixes an issue)

Checklist:

• I have met the contributing prerequisites
  • Assigned myself to this PR
  • Added the appropriate labels
  • Associated an issue: Issues and Pull Requests README #672
  • Read the Contributing guide: https://github.com/SpecterOps/BloodHound/wiki/Contributing
• I have ensured that related documentation is up-to-date
  • Open API docs
  • Code comments (GoDocs / JSDocs)
• I have followed proper test practices
  • Added/updated tests to cover my changes
  • All new and existing tests passed