Set updated_posture_page feature flag to true

[elikmiller]

Description

• Sets the updated_posture_page feature flag to true in the 6.3.0 migration file

Motivation and Context

This PR addresses: https://specterops.atlassian.net/browse/BED-5073

Why is this change required? What problem does it solve?

Enables the updated Posture page feature flag. For BHE use case only.

How Has This Been Tested?

Please describe in detail how you tested your changes.
Include details of your testing environment, and the tests you ran to
see how your change affects other areas of the code, etc.

No logical changes

Types of changes

• Chore (a change that does not modify the application functionality)
• Database Migrations

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