Create new custom role in UI
### Background
As an admin or group owner, I need to create role using new custom roles and permissions framework so that I am later able to assign it to a user.
Each role must use an existing role as a base. Permissions are additive only in nature.
New role must have a unique name.
### Location in Menu
<details>
<summary>SaaS</summary>

</details>
<details>
<summary>Self-Managed</summary>

</details>
### Mockups

#### Landing Page (?) - if no custom roles exist? Need clarification

#### Success - Role Created

### Availability & Testing
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What risks does this change pose to our availability? How might it affect the quality of the product? What additional test coverage or changes to tests will be needed? Will it require cross-browser testing?
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* Unit test changes
* Integration test changes
* End-to-end test change
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E2E tests should be added for creating a new custom role
issue