Add Enroll Edge Type to Path Finding

[spyr0-sec]

Description

Added the Enroll type to Edge Types as it was missing from Path Finding

Motivation and Context

This PR addresses: [GitHub issue]

Was not able to path find between node with enrollment rights to a Cert Template

How Has This Been Tested?

This has not been tested, I am hoping there is not more to fix this issue but hopefully you can confirm.

Screenshots (optional):

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist:

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

[StephenHinck]

See conversation https://github.com/SpecterOps/BloodHound/issues/799