[Documentation] Please clarify permissions needed to add an assign app roles

[chitturs]

Documentation related to component

Please check all that apply

• [ ] typo
• [ ] documentation doesn't exist
• [x] documentation needs clarification
• [ ] error(s) in the example
• [ ] needs an example

Description of the issue

The documentation for app role addition and assigning users and groups to the app role says that you need to sign in a "Cloud Application Administrator". This is misleading since the application owner has permissions to do this. Please explicitly clarify that application owner can add app roles (using app registration in portal or powershell) and assign users and groups to those roles (using enterprise applications in portal or powershell).