Some modules are missing appropriate headers

At a minimum, modules need appropriate headers for license checks such as:

<properties>
  <license-text.header>headers/AGPL-3-header.txt</license-text.header>
</properties>

Modules missing headers:

1. ONgDB - Enterprise Build
2. ONgDB - Enterprise Graph Database Auth Plugin API
3. ONgDB - Backup Tool
4. ONgDB - Causal Clustering
5. ONgDB - Cypher Acceptance
6. ONgDB - Cypher Compatibility Specification Suite
7. ONgDB - Enterprise Cypher
8. ONgDB - Cypher Physical Planning
9. ONgDB - Cypher Slotted Runtime
10. ONgDB - Cypher Specification Suite Tools
11. ONgDB - Deferred Locks
12. ONgDB - High Availability
13. ONgDB - Enterprise Graph Database Kernel Features
14. ONgDB - Low Level Tools
15. ONgDB - Stress Tests