Bamboo Specs YAML documentation must inform required properties

Issue Summary

Bamboo Specs YAML documentation must be updated informing required properties, so users when building their /bamboo-specs/bamboo.(yml|yaml) can have a better understanding to the reason why their YAML file is not working as expected.

As an example, when setting up Environment permissions (ernvironment-permissions:), it is mandatory to declare Deployment permissions (deployment-permission:) in the same YAML file.

Environment

• Bamboo v6.9.0 or above
• Bamboo Specs YAML version 2

Steps to Reproduce

1. Follow the steps on Tutorial: Bamboo Specs YAML stored in Bitbucket Server
2. Describe YAML as per following (aiming to set up Environment permissions):

   ---
   version: 2
   deployment: My deployment
   
   environment-permissions:
     - Test:
       - users:
         - admin
       permissions:
         - view
         - edit
         - deploy
   

Expected Results

User "admin" should have "view", "edit" and "deploy" permissions granted.

Actual Results

Error gets thrown:

Bamboo YAML import failed: Invalid format of the YAML file: mapping values are not allowed here
 in 'reader', line 5, column 24:
    environment-permissions:
                           ^

Workaround

Deployment permissions (deployment-permission:) must be provided as it is required by Bamboo Specs YAML version 2. You shall find an example to /bamboo-specs/bamboo.(yml|yaml) below:

---
version: 2
deployment: My deployment

deployment-permissions: 
  - users:
      - admin

environment-permissions:
  - Test:
    - users:
      - admin
    permissions:
      - view
      - edit
      - deploy